PD-L1 expression in head and neck squamous cell carcinoma and its clinical significance: A prospective observational study from a tertiary care centre.

BACKGROUND: Programmed Death Ligand 1 (PD-L1) expression in tumor cells contribute to tumor immunity and therapies directed against it, have shown encouraging results in recent years. As there is limited data on the significance of PD-L1 expression in Head and Neck Squamous Cell Carcinoma (HNSCC) from India, we aimed to study the PD-L1 expression and its relation with different clinic-pathological parameters in patients of HNSCC from a tertiary care center in Eastern India. METHODS: A prospective evaluation of HNSCC patients diagnosed and managed at our center over a period of two and half years, was performed. PD-L1 expression in formalin fixed-paraffin embedded tumor tissue specimens was measured using SP-263 (Ventana) and 22C3 (Dako). A PD-L1 expression of <1%, 1-19%, ≥20% were considered negative, low, and high expression, respectively, and was correlated with various parameters. RESULTS: A total of 71 patients (mean age 50.8 ± 13.3 years, 86% males) were diagnosed with HNSCC (buccal mucosa-28, tongue-22, rest of oral cavity-8, larynx-7, nasopharynx-6). The tumor was poorly differentiated in 12 (17%). PD-L1 positivity was seen in a total of 51 (71.8%) patients (1-19%:18, ≥20%:33). Thirty (85.7%) patients among those aged <50 years and 58.3% of those aged ≥50 years showed PD-L1 positivity which was significant (P = 0.01). There were no statistically significant differences in PD-L1 positivity with respect to gender, tobacco use, tumor grade as well as tumor and nodal stage. Median follow up duration was 18 months (range 3-31 months) and there was significant difference in overall survival among PD-L1 positive and negative groups (31 vs 24 months; log rank P = 0.03). CONCLUSIONS: 72% of HNSCC patients in our cohort showed PD-L1 positivity and it was not associated with any patient demographic characteristics or aggressive pathological features. Positive PD-L1 expression may have a beneficial effect on overall survival in HNSCC.

PD-L1 expression and its significance in advanced NSCLC: real-world experience from a tertiary care center.

BACKGROUND: Targeted therapies against programmed death ligand-1 (PD-L1) in non-small cell lung cancer (NSCLC) have revolutionized the management in recent years. There is paucity of data on the significance of PD-L1 expression in NSCLC from India. We aimed to study the prevalence of PD-L1 expression and its relation with different clinico-pathological parameters in advanced NSCLC from a tertiary care center in Eastern India. METHODS: All consecutive patients with advanced NSCLC diagnosed from January 2020 to December 2021 were prospectively evaluated for PD-L1 expression in formalin fixed-paraffin embedded tumor tissue specimens using immunohistochemistry analysis. A PD-L1 expression of < 1%, 1-49%, and ≥ 50% were considered negative, low, and high expression positive respectively, and association with various parameters was performed. RESULTS: Out of the 94 patients (mean age 59.6 ± 14 years and 63.8% males), PD-L1 positivity was seen in 42 (44.7%) patients, with low positivity (1-49%) in 29 patients and high positivity (≥ 50%) in 13 patients. Epidermal Growth Factor Receptor (EGFR) mutations were seen in 28 patients (29.8%). There were no significant differences in PD-L1 positivity with respect to gender, age, and molecular mutation status. PD-L1 positivity was significantly associated with tobacco use (p = 0.04), advanced tumor stage (p < 0.001), and higher nodal stage (p < 0.001). Median overall survival in the cohort was 17 months and it was not significantly different between the PD-L1 positive and negative groups. CONCLUSIONS: Forty-five percent of advanced NSCLC patients in our cohort showed positive PD-L1 expression and it is associated with tobacco use and aggressive tumor characteristics.

Plant histone variants at the nexus of chromatin readouts, stress and development.

Histones are crucial proteins that are involved in packaging the DNA as condensed chromatin inside the eukaryotic cell nucleus. Rather than being static packaging units, these molecules undergo drastic variations spatially and temporally to facilitate accessibility of DNA to replication, transcription as well as wide range of gene regulatory machineries. In addition, incorporation of paralogous variants of canonical histones in the chromatin is ascribed to specific functions. Given the peculiar requirement of plants to rapidly modulate gene expression levels on account of their sessile nature, histones and their variants serve as additional layers of gene regulation. This review summarizes the mechanisms and implications of distribution, modifications and differential incorporation of histones and their variants across plant genomes, and outlines emerging themes.

Plant polymerase IV sensitizes chromatin through histone modifications to preclude spread of silencing into protein-coding domains.

Across eukaryotes, gene regulation is manifested via chromatin states roughly distinguished as heterochromatin and euchromatin. The establishment, maintenance, and modulation of the chromatin states is mediated using several factors including chromatin modifiers. However, factors that avoid the intrusion of silencing signals into protein-coding genes are poorly understood. Here we show that a plant specific paralog of RNA polymerase (Pol) II, named Pol IV, is involved in avoidance of facultative heterochromatic marks in protein-coding genes, in addition to its well-established functions in silencing repeats and transposons. In its absence, H3K27 trimethylation (me3) mark intruded the protein-coding genes, more profoundly in genes embedded with repeats. In a subset of genes, spurious transcriptional activity resulted in small(s) RNA production, leading to post-transcriptional gene silencing. We show that such effects are significantly pronounced in rice, a plant with a larger genome with distributed heterochromatin compared with Arabidopsis Our results indicate the division of labor among plant-specific polymerases, not just in establishing effective silencing via sRNAs and DNA methylation but also in influencing chromatin boundaries.

A conserved SNP variation in the pre-miR396c flanking region in Oryza sativa indica landraces correlates with mature miRNA abundance.

Plant precursor miRNAs (pre-miRNA) have conserved evolutionary footprints that correlate with mode of miRNA biogenesis. In plants, base to loop and loop to base modes of biogenesis have been reported. Conserved structural element(s) in pre-miRNA play a major role in turn over and abundance of mature miRNA. Pre-miR396c sequences and secondary structural characteristics across Oryza species are presented. Based on secondary structure, twelve Oryza pre-miR396c sequences are divided into three groups, with the precursor from halophytic Oryza coarctata forming a distinct group. The miRNA-miRNA* duplex region is completely conserved across eleven Oryza species as are other structural elements in the pre-miRNA, suggestive of an evolutionarily conserved base-to-loop mode of miRNA biogenesis. SNPs within O. coarctata mature miR396c sequence and miRNA* region have the potential to alter target specificity and association with the RNA-induced silencing complex. A conserved SNP variation, rs10234287911 (G/A), identified in O. sativa pre-miR396c sequences alters base pairing above the miRNA-miRNA* duplex. The more stable structure conferred by the 'A10234287911' allele may promote better processing vis-à-vis the structure conferred by 'G10234287911' allele. We also examine pri- and pre-miR396c expression in cultivated rice under heat and salinity and their correlation with miR396c expression.

Cultivar-specific miRNA-mediated RNA silencing in grapes.

MAIN CONCLUSION: In-depth comparative degradome analysis of two domesticated grape cultivars with diverse secondary metabolite accumulation reveals differential miRNA-mediated targeting. Small (s)RNAs such as micro(mi)RNAs and secondary small interfering (si) often work as negative switches of gene expression. In plants, it is well known that miRNAs target and cleave mRNAs that have high sequence complementarity. However, it is not known if there are variations in miRNA-mediated targeting between subspecies and cultivars that have been subjected to vast genetic modifications through breeding and other selections. Here, we have used PAREsnip2 tool for analysis of degradome datasets derived from two contrasting domesticated grape cultivars having varied fruit color, habit and leaf shape. We identified several interesting variations in sRNA targeting using degradome and 5'RACE analysis between two contrasting grape cultivars that was further correlated using RNA-seq analysis. Several of the differences we identified are associated with secondary metabolic pathways. We propose possible means by which sRNAs might contribute to diversity in secondary metabolites and other development pathways between two domesticated cultivars of grapes.

A conserved sequence signature is essential for robust plant miRNA biogenesis.

Micro (mi)RNAs are 20-22nt long non-coding RNA molecules involved in post-transcriptional silencing of targets having high base-pair complementarity. Plant miRNAs are processed from long Pol II-transcripts with specific stem-loop structures by Dicer-like (DCL) 1 protein. Although there were reports indicating how a specific region is selected for miRNA biogenesis, molecular details were unclear. Here, we show that the presence of specific GC-rich sequence signature within miRNA/miRNA* region is required for the precise miRNA biogenesis. The involvement of GC-rich signatures in precise processing and abundance of miRNAs was confirmed through detailed molecular and functional analysis. Consistent with the presence of the miRNA-specific GC signature, target RNAs of miRNAs also possess conserved complementary sequence signatures in their miRNA binding motifs. The selection of these GC signatures was dependent on an RNA binding protein partner of DCL1 named HYL1. Finally, we demonstrate a direct application of this discovery for enhancing the abundance and efficiency of artificial miRNAs that are popular in plant functional genomic studies.

Axial pattern flaps, using the deep circumflex iliac artery, superficial brachial and cranial superficial epigastric direct cutaneous arteries in the dog.

Three dogs (Boxer, Labrador Retriever and German Shepherd) between the age of 7-10 years were presented with the history of tumour masses on right caudo-lateral thigh, right cranial forearm and left cranial and caudal thoracic mammary gland region, respectively. Fine needle aspiration cytology of the tumour masses and the sentinel regional lymph nodes were done. Plain radiography was done to rule out distant metastasis. In all the three cases the tumour masses were large in size, firmly adherent to the tissues underneath and sufficient loose skin was not available to close the skin defect following surgery. Hence axial pattern flaps were chosen to close the skin defect, following wide margin excision of tumour masses, leaving 3 cm from all the dimensions including healthy tissue. Deep circumflex iliac axial pattern flap, superficial brachial axial pattern flap and cranial superficial epigastric axial pattern flap were chosen to close the skin defect in case 1, case 2 and case 3, respectively. Post-operatively the dogs were admitted in in-patient unit for 5 days to restrict movement of the dog for immobilization of the flap and for wound dressing. All the cases recovered uneventfully with few complications.

Outcomes of levator advancement and Müller muscle-conjunctiva resection for the repair of upper eyelid ptosis.

Both the Müller muscle-conjunctiva resection (MMCR) and levator advancement (LA) procedures can be used to manage ptosis in patients with good levator function. The aim of this article is to evaluate the efficacy and cosmetic outcomes of the two procedures. The clinical records of 29 consecutive eyelids of 26 patients undergoing MMCR and 30 eyelids of 23 patients undergoing LA were analysed. Eleven (42%) in the LA group and 9 (39%) in the MMCR group were male. The preoperative eyelid measurements were significantly different in the LA compared to the MMCR groups, in terms of palpebral aperture (PA) (6.3 vs 7.4, p = 0.01), marginal reflex distance 1 (MRD1) (-0.1 vs 1.5, p < 0.001) and levator function (LF) (12.1 vs 13.4, p = 0.03). The MRD1 1 month post-surgery was slightly less in the LA group compared to the MMCR group (2.6 vs 3.18 mm, p = 0.047) but not significantly different at months 3 and 6. The final change in MRD1 was significantly higher in the LA group (2.93 vs 1.76, p = 0.004). The MMCR group had a lower incidence of lid contour abnormalities (0% vs 20%, p = 0.01) and overcorrection (0% vs 13%, p = 0.04). There was no statistically significant difference in the rates of undercorrection in either group. Both the MMCR as well as LA procedures are effective for mild to moderate ptosis in patients with good levator function. Patients undergoing MMCR had higher success rates, better preservation of the natural lid contour, and a lower incidence of overcorrection than patients undergoing LA.

[Adolescent onset obsessive compulsive disorder presented as dissociative disorders: role of drug assisted interview]. / Ergenlikte Baslayan Dissosiyatif Bozukluga Benzeyen Obsesif Kompülsif Bozukluk: Ilaç Destekli Görüsmenin Rolü

Paediatric Obsessive Compulsive Disorder (OCD) is still under-diagnosed, despite significant advances made in identifying obsessive-compulsive symptoms. The authors report a case of adolescent-onset OCD presenting as a mixed dissociative disorder. The drug assisted interview provided a breakthrough in revising the correct diagnosis of the clinical condition. The psychopathology of the patient contains sexual and aggressive obsessions without any compulsions. Adolescent OCD can present as dissociative disorders and a thiopentone interview can be helpful in revealing the distress associated with OCD.

First isolations in India of Candida nivariensis, a globally emerging opportunistic pathogen.

We randomly screened 363 yeast isolates during 2008 for their ability to form white colonies on CHROM agar Candida medium. Two of these isolates (0.5%) were identified as Candida nivariensis based on detailed phenotypic characterization and DNA sequencing. One was recovered from the sputum of an HIV-positive patient with a pneumonic lesion and the second from the blood of a diabetic with oropharyngeal lesions. Direct DNA sequencing of the D1/D2 region of 28S rRNA gene and/or the internal transcribed spacer (ITS) regions of rDNA confirmed that both of the isolates were C. nivariensis. The carbohydrate assimilation profiles with the ID 32 C and VITEK 2 yeast identification systems revealed only glucose assimilation. In vitro antifungal susceptibility profiles by broth microdilution and Etest methods revealed susceptibility of both isolates to fluconazole, itraconazole, voriconazole, amphotericin B and 5-flucytosine, with low MICs for posaconazole and caspofungin. These results document the occurrence of Candida nivariensis for the first time in India and focus on its potential as an opportunistic human pathogen.

Occurrence of organochlorine pesticide residues in green mussel (Perna viridis L.) and water from Ennore creek, Chennai, India.

Green mussel (Perna viridis) and water samples were collected from Ennore creek, Chennai by seasonal sampling and analyzed for organochlorine pesticide residues (OCPs) like dichloro-diphenyl-trichloroethane (DDT) and its metabolites, isomers of hexachlorocyclohexane (HCH) and endosulfan. These residues were analyzed by using gas chromatograph (GC) with microECD. In the present study, mussel samples showed very low concentrations of OCPs in the statistical order of DDT (5.83 ng g(-1) wet tissue)>endosulfan (2.84 ng g(-1) wet tissue)>HCH (2.34 ng g(-1) wet tissue). Concentrations of OCPs in water samples were in the statistical order of endosulfan (29.21 ng L(-1))>HCH (17.14 ng L(-1))>DDT (14.63 ng L(-1)). To our knowledge, this is the first report on the seasonal variation of OCPs and especially the quantification of endosulfan in Ennore Creek. The present study recommends that continuous monitoring in Ennore creek is necessary to assess possible impact on human health.

Intraocular pressure elevation after simple pars plana vitrectomy.

PURPOSE: The purpose of the study is to determine the incidence, timing, and severity of variability in the intraocular pressures (IOPs) from baseline after simple pars plana vitrectomy. METHODS: A prospective study was performed in 25 consecutive patients undergoing simple pars plana vitrectomy. Intraocular pressures were measured before surgery, immediately after surgery, and then at 2, 4, 6, 12, and 24 hours after surgery. RESULTS: The mean IOP was elevated significantly 2 hours after surgery when compared with the mean immediate postoperative IOP (30.3 mmHg +/- 11.0 mmHg vs. 17.4 mmHg +/- 7.0 mmHg, P < 0.001). A steady decline was seen at all succeeding timepoints. The 24-hour mean (17.3 mmHg +/- 4.3 mmHg, P = 0.923) was similar to baseline. Ninety-two percent of eyes had a 2-hour postoperative IOP that was higher than the IOP at the completion of surgery. Forty percent of patients required medical management for IOP greater than or equal to 30 mmHg. CONCLUSIONS: Significant IOP elevation can occur after simple pars plana vitrectomy. The optimal time for detecting the pressure rise during the first 24 hours is 2 hours after surgery.