Biosynthesis of bacteriocin BacZY05-silver nanoconjugates and evaluation of their antibacterial properties.

Bacteriocins are antimicrobial peptides produced by bacteria to prevent the growth of pathogens. Combining bacteriocins with metal nanoparticles, like silver nanoparticles (AgNPs), has developed into a viable strategy to get over bacteriocin limitations. In this study, bacteriocin BacZY05 was extracted from Bacillus subtilis ZY05 and purified using various techniques. The resulting purified bacteriocin was then combined with silver nanoparticles to form bacteriocin silver nanoconjugates (BacZY05-AgNPs). The physicochemical properties of the BacZY05-AgNPs were characterized using various analytical techniques. The mean diameter of the synthesized AgNPs was approximately 20-60 nm with an oval or spherical shape. The antimicrobial activity of the BacZY05-AgNPs was evaluated against several indicator strains by their zone of inhibition (ZOI), using the agar well diffusion method. Compared to bacteriocin (ZOI- 13 to 20 mm) and AgNPs (ZOI- 10-22 mm) alone, the antibacterial activity data demonstrated a 1.3-1.5-fold increase in the activity of bacteriocin-nanoconjugates (ZOI- 22 to 26 mm). For Staphylococcus aureus MTCC3103 and Klebsiella pneumoniae MTCC109, BacZY05-capped AgNPs exhibited the lowest minimum inhibitory concentration (MIC), measuring 10.93 µg/mL. For Salmonella typhi NCIM2501, the MIC was 28.75 µg/mL. The highest MIC value was 57.5 µg/mL for Escherichia coli DH5α and Vibrio cholerae MTCC3909. With BacZY05-capped AgNPs, the lowest minimum bactericidal concentration (MBC) of 28.75 µg/mL was observed for Staphylococcus aureus MTCC31003. In the cases of Salmonella typhi NCIM2501 and Klebsiella pneumoniae MTCC109 concentration was 57.5 µg/mL. Vibrio cholerae MTCC3909 and Escherichia coli DH5α had the highest MBC values at 115 µg/mL.

Male-to-Female Gender Affirmation Vaginoplasty via Laparoscopic Pedicled Peritoneal Flap-An Initial Experience.

Objective The objective of this study was to describe our early experience with laparoscopic pedicled peritoneal flap in patients undergoing male-to-female gender affirmation vaginoplasty. Methods This is a case series of five patients who underwent laparoscopic pedicled peritoneal flap vaginoplasty for gender reaffirmation from October 2020 to July 2021. The clinical and functional outcomes were recorded. Results Two patients underwent the surgery as a primary procedure, and three patients underwent surgery as a secondary deepening procedure after failed penile skin inversion. There were no complications after surgery, and the median length of hospital stay was 3 days. No patient developed vaginal stenosis in 6-month follow-up period, and the median vaginal depth was 6 inches with a healthy vaginal surface. Conclusion Laparoscopic pedicled peritoneal flap can be considered as a first choice in gender affirmation surgeries for patients with inadequate penoscrotal skin or failed penile skin inversion.

Laparoscopic versus open extended cholecystectomy with bi-segmentectomy (s4b and s5) in patients with gallbladder cancer.

INTRODUCTION: The outcome of laparoscopic extended cholecystectomy (EC) with wedge hepatic resection (LECW) in patients with gallbladder cancer (GBC) has been compared with that of open EC with wedge hepatic resection (OECW), but studies comparing laparoscopic EC with bi-segmentectomy (LECB) with open EC with bi-segmentectomy (OECB) are lacking. PATIENTS AND METHODS: This retrospective study comprised of 68 patients with GBC who were offered either LECB or OECB from July 2011 to July 2018. Patients were divided into laparoscopic group (LG) and open group (OG), and appropriate statistical methods were used for comparison. RESULTS: Out of the total 68 patients, 30 patients were in LG and 38 patients were in OG. Demographic, clinical and biochemical characteristics were similar except significantly higher number of male patients in OG (P = 0.01). In LG versus OG, the mean operation time was 286 versus 274 min (P = 0.565), mean blood loss was 158 versus 219 ml (P = 0.006) and mean hospital stay was 6.4 versus 9 days (P = 0.0001). The complication rate was 16.6% in LG and 31.5% in OG, but this difference was not statistically significant (P = 0.259). The median number of lymph nodes was 12 in both LG and OG (P = 0.62). Distribution of patients among American Joint Committee on Cancer stages I to IV was similar in both the groups (P = 0.5). Fifty percent of the patients in both the groups received adjuvant treatment (P = 1). In LG versus OG, the recurrence rate was 20% versus 28.9% (P = 0.4), mean recurrence-free survival was 48 months versus 44 months (P = 0.35) and overall survival was 51 months versus 46 months (P = 0.45). In LG versus OG, 1, 3 and 5-year survival was 96% versus 94%, 79% versus 72% and 79% versus 62% (P = 0.45). The median follow-up was statistically significantly shorter (24 vs. 36 months) in LG versus OG (P = 0.0001). CONCLUSIONS: The oncological outcome and survival after LECB in patients with resectable GBC is not inferior to that after OECB. Laparoscopic approach has a potential to improve perioperative outcome in patients with GBC.

Raised CA19-9 and CEA have prognostic relevance in gallbladder carcinoma.

BACKGROUND: Role of tumor markers in gall bladder carcinoma (GBC) is not well established. We evaluated the prognostic value of carbohydrate antigen 19-9 (CA19-9) and carcinoma embryonic antigen (CEA) in patients with GBC. METHODS: Of the 225 patients of GBC enrolled,176 patients were included in the study (excluded 49 patients with jaundice). Patients were divided into 3 groups; resectable n = 92, unresectable n = 17, metastatic n = 67. The clinico-pathological characteristics, tumor markers and survival data were analysed. The cutoff values of CA19-9 & CEA for predicting metastases were computed using receiver operating characteristic curve. Kaplan Meir survival and Cox regression analysis were done for factors predicting survival and recurrence. RESULTS: The median value of Ca19-9 was significantly higher in metastatic group [resectable: 21.3, unresectable: 53.9 and metastatic: 79; p < 0.001] but not for CEA [3.5, 7.8 and 5 ng/ml (p = 0.20)]. A cutoff value of 72 IU/ml for CA19-9, 5 ng/ml for CEA had a sensitivity and specificity of 52 and 80%, 51 and 72% respectively for detection of metastatic disease. Median, 3-year & 5-year survival were significantly lower in patients with CEA > 4 (p = 0.041), Ca19.9 > 37 (p = 0.019), T3/T4 (p = 0.001), node positive (p = 0.001) and presence of perineural invasion (p = 0.001). However, on multivariate analysis, only Ca19.9 > 37 predicted recurrence (p = 0.002, HR 5.8). CONCLUSIONS: Raised CA19.9 and CEA predict metastatic disease in patients with GBC without jaundice with a high specificity and may help in prognostication of the patient. CA19-9 was better than CEA in prediction of tumor burden and in predicting recurrence.

A rapid and simple ultra high performance liquid chromatography method for the simultaneous determination of methoxyphenol derivatives involved in the eugenol catabolic pathway.

An efficient ultra high performance liquid chromatography method of separation was developed for the analysis of six important methoxyphenol derivatives involved in the eugenol catabolic pathway. In the present study, an Acquity UPLC BEH C18 column was used for the chromatographic separation of the industrially important phenolic compounds such as vanillin, vanillic acid, ferulic acid, coniferyl alcohol, and coniferyl aldehyde obtained during microbial transformation of eugenol. Eluted components were identified using the dual wavelength (254 and 310 nm) UV detector. A gradient method of elution using mobile phase of aqueous 1 mM trifluoroacetic acid (Solvent A) and methanol (Solvent B) at a flow rate of 0.3 mL/min separated all the five intermediate methoxyphenol derivatives along with their precursor eugenol within 15 min with stable baseline resolution. Method validation was performed for the accurate quantification of vanillin, coniferyl aldehyde, and eugenol using the parameters of linearity, specificity, precision, limit of detection, limit of quantification, and robustness. The developed method would be helpful for clear separation and identification of the five most important intermediate metabolites of the eugenol catabolism pathway.

Utilization of Gastric Conduit in the Management of Combined Corrosive Esophageal and Stomach Stricture.

BACKGROUND: Corrosive stricture of esophagus may be associated with variable involvement of stomach. We analyzed the outcome of gastric conduit used in the management of corrosive esophageal stricture with concomitant antro-pyloric stricture. STUDY DESIGN: Among 101 esophageal replacements performed, 53 patients had combined esophagus and stomach strictures. Colon was used as a conduit in 43 patients, while stomach was used in ten patients. Indications, perioperative complications and early/late outcomes of patients with gastric pull-up were reviewed and compared with those undergone colon pull-up. RESULTS: The indications of using gastric conduit were impromptu in four patients [colonic conduit ischemia (n = 2) and an oversight of antro-pyloric stricture after forming the gastric conduit (n = 2)]. Six patients had preconceived gastric conduit (distal antro-pyloric stricture with distended stomach). The median age was 29 years (range 16-50), and median BMI was 15.4 kg/m2 (range 14.5-20.1). The stomach was drained using loop gastrojejunostomy (n = 7) or Roux-en-Y gastrojejunostomy (n = 3). One patient died due to sepsis secondary to anastomotic leak. Median hospital stay was 9 days (range 7-22). At median follow-up of 25 months (range 14-80), the remaining nine patients are able to have solid diet and have gained weight. The level of esophageal stricture was low (p = 0.01), and duration of surgery (p = 0.02) and median hospital stay (p = 0.04) were significantly less in patients with gastric conduit plus drainage as compared to patients undergone colonic pull-up. CONCLUSION: Gastric conduit in a subject with distal antro-pyloric stricture can be used safely along with gastrojejunostomy in selected patients of corrosive esophageal stricture.

Specificity and Ligand Affinities of the Cocaine Aptamer: Impact of Structural Features and Physiological NaCl.

The cocaine aptamer has been seen as a good candidate for development as a probe for cocaine in many contexts. Here, we demonstrate that the aptamer binds cocaine, norcocaine, and cocaethylene with similar affinities and aminoglycosides with similar or higher affinities in a mutually exclusive manner with cocaine. Analysis of its affinities for a series of cocaine derivatives shows that the aptamer specificity is the consequence of its interaction with all faces of the cocaine molecule. Circular dichroism spectroscopy and 2-aminopurine (2AP) fluorescence studies show no evidence of large structural rearrangement of the cocaine aptamer upon ligand binding, which is contrary to the general view of this aptamer. The aptamer's affinity for cocaine and neomycin-B decreases with the inclusion of physiological NaCl. The substitution of 2AP for A in position 6 (2AP6) of the aptamer sequence eliminated the effect of NaCl on its affinities for cocaine and analogues, but not for neomycin-B, showing a selective effect of 2AP substitution on cocaine binding. The affinity for cocaine also decreased with increasing concentrations of serum or urine, with the 2AP6 substitution blunting the effect of urine. Its low affinities for cocaine and metabolites and its ability to bind irrelevant compounds limit the opportunities for application of this aptamer in its current form as a selective and reliable sensor for cocaine. However, these studies also show that a small structural adjustment to the aptamer (2AP exchanged for adenine) can increase its specificity for cocaine in physiological NaCl relative to an off-target ligand.

Enhanced production of bacteriocin by Bacillus subtilis ZY05.

Bacteriocin-producing strains were isolated from the soil of the rice field, screened out using an agar-well diffusion assay against six indicator bacterial strains, and the highest among them was selected for further investigation. The study focuses on how different growing conditions affect bacteriocin production. One-parameter-at-a-time (OPAT) and a central composite design of response surface methodology (RSM) were used to perform the optimization in two steps. In the OPAT trials, bacteriocin synthesis was elevated by 29%, 45%, and 34%, by employing sucrose as a carbon source and changing the NaCl concentration and pH at 7, respectively. To determine the linear, squared, and interaction correlations among the process variables to predict the ideal conditions for production, a four-factor central composite design (CCD) of RSM was used. It was determined that the analysis of variance (ANOVA), which produces a recognized model using RSM, is sufficient to describe bacteriocin production regarding activity (R2 = 0.9606). The ideal conditions for increased production were 1.51% sucrose concentration, 1.59% NaCl concentration, pH 6.35, and 28.66 (about 29) hours of incubation. The value predicted by RSM (4051.55 AU/mL) was approximately two times greater than the value of a non-optimized medium. The experimental value of 4403.85 AU/mL was closer to the expected value. According to the data, increasing bacteriocin activity required employing the ideal sucrose concentration, NaCl concentration, and incubation time. The partially purified bacteriocin was found stable at temperatures between 24 and 50 °C and at pH 5-8. The molecular weight purified bacteriocin was determined to be between 13 and 35 kDa.

Production of natural value-added compounds: an insight into the eugenol biotransformation pathway.

During the past few years, the production of natural value-added compounds from microbial sources has gained tremendous importance. Due to an increase in consumer demand for natural products, various food and pharmaceutical industries are continuously in search of novel metabolites obtained from microbial biotransformation. The exploitation of microbial biosynthetic pathways is both feasible and cost effective in the production of natural compounds. The environmentally compatible nature of these products is one major reason for their increasing demand. Novel approaches for natural product biogeneration will take advantage of the current studies on biotechnology, biochemical pathways and microbiology. The interest of the scientific community has shifted toward the use of microbial bioconversion for the production of valuable compounds from natural substrates. The present review focuses on eugenol biotransformation by microorganisms resulting in the formation of various value-added products such as ferulic acid, coniferyl alcohol, vanillin and vanillic acid.

Cowden Syndrome With Gall Bladder Polyps and Incidental Gall Bladder Carcinoma.

Cowden syndrome is an uncommon autosomal dominant disorder characterized by multiple hamartomas in various tissues. It is associated with germline mutation in the phosphatase and tensin homolog (PTEN) gene. It has an increased risk of malignancies of various organs (commonly breast, thyroid, and endometrium) and benign overgrowth of tissues like skin, colon, and thyroid. Here, we present a case of Cowden syndrome in a middle-aged female who presented with acute cholecystitis with gall bladder polyps along with intestinal polyps. She underwent total proctocolectomy with ileal pouch-anal anastomosis (IPAA) with diversion ileostomy and cholecystectomy, which was further proceeded to completion of radical cholecystectomy based on the final histopathology report as incidental gall bladder carcinoma. To the best of our knowledge, this association is seen for the first time in the literature. In Cowden syndrome, patients should be counseled for regular follow-up and instructed to be aware of the signs and symptoms of different types of cancers with higher incidence.

Aptamer functionalized microcantilever sensors for cocaine detection.

A cocaine-specific aptamer was used as a receptor molecule in a microcantilever-based surface stress sensor for detection of cocaine molecules. An interferometric technique that relies on measuring differential displacement between two microcantilevers (a sensing/reference pair) was utilized to measure the cocaine/aptamer binding induced surface stress changes. Sensing experiments were performed for different concentrations of cocaine from 25 to 500 µM in order to determine the sensor response as a function of cocaine concentration. In the lower concentration range from 25 to 100 µM, surface stress values increased proportionally to coverage of aptamer/cocaine complexes from 11 to 26 mN/m. However, as the cocaine concentration was increased beyond 100 µM, the surface stress values demonstrated a weaker dependence on the affinity complex surface coverage. On the basis of a sensitivity of 3 mN/m for the surface stress measurement, the lowest detectable threshold for the cocaine concentration is estimated to be 5 µM. Sensing cantilevers could be regenerated and reused because of reversible thermal denaturation of aptamer.

Bi-segmentectomy versus wedge hepatic resection in extended cholecystectomy for T2 and T3 gallbladder cancer: A matched case-control study.

BACKGROUNDS/AIMS: Extended cholecystectomy (EC) is the mainstay of treatment in most patients with potentially curable gallbladder cancer (GBC). The optimum extent of hepatic resection in EC is debatable. METHODS: This retrospective study was conducted on patients with GBC who received EC from May 2009 to February 2019. Based on the extent of hepatic resection, patients were divided into ECB (EC involving bi-segmentectomy s4b&5) and ECW (EC involving wedge hepatic resection) groups. Patients with T1 GBC, T4 GBC, and benign diseases were excluded. Post-exclusion, both groups were matched for T and N stage. Matched groups were then compared. RESULTS: Out of a total of 161 patients who received EC, 86 patients had ECB and 75 patients had ECW. After exclusion and matching, both ECB and ECW groups had 35 patients. Their demographic and clinical profiles were comparable. Surgical blood loss (p = 0.005) and postoperative complication rate (p = 0.035) were significantly less in the ECB group. For ECB vs. ECW, mean recurrence-free survival (RFS) was 58.2 months vs. 42.3 months (p = 0.264) and overall survival (OS) was 61.5 months vs. 43.4 months (p = 0.161). On univariate analysis, higher T and N stages were associated with poor prognosis. On multivariate analysis, higher T stage, N stage, and American Society of Anaesthesiologists grade were associated with poor RFS and OS. CONCLUSIONS: The survival after ECB for T2 and T3 GBC was not significantly superior to that after ECW. However, surgical blood loss and postoperative complications were lower following ECB.

Trends and clinico-epidemiological profile of COVID-19 patients at a designated COVID-19 hospital in Delhi, North India.

BACKGROUND: The coronavirus disease (COVID-19) presents across a spectrum of signs and symptoms and shows clinico-epidemiological predilections (elderly, those with comorbidities). Delhi is among the highest burden states in India. OBJECTIVES: To report the case detection trends and clinico-epidemiological profile of patients tested positive at a designated COVID-19 hospital in Delhi in Northern India. METHODS: Using an observational (descriptive design) we analyzed data from the electronic medical records of the hospital. All individuals testing positive for SARS-CoV-2 RNA using reverse transcription polymerase chain reaction (RT-PCR) between 17th March and 07th May 2020 (both dates inclusive) were included. Case detection trend (7-day moving averages) was plotted. Clinico-epidemiological profile of patients was summarized statistically. RESULTS: Total 308 positive cases were enrolled in this study. The median age of participants was 48 years (09-95 years) men (47.9 ± 16.4 years) and women (43.5 ± 14.0 years). Men to women ratio was 3.4:1 with a statistically significant difference (P < 0.001). During the study timeframe, 166 (54.0%) patients had an outcome: 11 (6.6%; 95% CI: 3.4-11.6) expired and 155 recovered (recovery rate: 93.4%; 95% CI: 88.5-96.7). Chance of death was significantly associated with the higher age group (P = 0.005). The commonest clinical symptoms noted were fever (38.9%) and cough (38.6%). Majority (56.6%) had mild to moderate symptoms, 12.6% had severe symptoms and the remaining were asymptomatic (30.8%). 31 patients (26.05%) needed ICU care. Total 119 patients (38.6%) had various preexisting comorbidities, most commonly diabetes mellitus (35.0%) and hypertension (34.0%). However, the comorbidities were not associated with age (P = 1.000). CONCLUSION: Triangulation of data and careful analysis of trends in designated COVID-19 hospitals and other institutional settings may help inform surge preparedness and care provisioning. Stringent containment strategies must continue as the pandemic is intensifying.

Solid Pseudopapillary Neoplasm of the Pancreas Clinicopathological Characteristics and Long-Term Outcome: a Single-Center Experience.

Solid pseudopapillary neoplasm is a rare tumor of the pancreas. These tumors are considered to have low malignant potential with good prognosis. Due to its rarity, details about clinical presentation and management of the disease are not very clear. This study aims to share our experience and to describe management of the disease. We retrospectively evaluated patients 13 patients diagnosed with SPT on histopathological examination of resected specimen. Data on their clinicopathological, management-related factors, and follow-up was collected. All the patients were females, with a median age of 20 years. Abdominal pain was the most common presentation. The mean tumor size was 6.5 cm and majority of tumors were located in the head region. R0 resection was obtained in all the patients. All patients were disease-free with a median follow-up of 68 months. Excellent prognosis can be achieved with a margin-negative resection in these tumors. Adjacent organ or vascular involvement is not a contraindication for surgical resection.

Histological changes in intestine in semichronic diarrhoea induced by lactose enriched diet in rats: effect of Diarex-Vet.

Efficacy of Diarex-Vet (The Himalaya Drug Company, Makali, Bangalore, India) was evaluated histologically in semichronic diarrhoea induced by lactose enriched diet in rats. The rats in different groups were given lactose enriched diet alone for 2 days before starting the treatment with Diarex-Vet at a dose of 250, 500 and 750 mg/kg body weight along with lactose enriched diet for 5 days. Animals were euthanised at the end of 5 days of treatment and histological changes were observed in the ileum, caecum and colon. Semiquantitative analysis of goblet cells in intestines showed dose dependent response among the treated groups. The morphological changes were comparable to normal in the group given 750 mg/kg body wt Diarex-Vet. The effects observed were attributed to the lactase like analogous activity of Diarex-Vet or the inhibition of the osmotic processes in the intestinal lumen thereby reducing the morphological changes in the intestines.

Microbial transformation of ferulic acid to vanillic acid by Streptomyces sannanensis MTCC 6637.

Streptomyces sannanensis MTCC 6637 was examined for its potentiality to transform ferulic acid into its corresponding hydroxybenzoate-derivatives. Cultures of S. sannanensis when grown on minimal medium containing ferulic acid as sole carbon source, vanillic acid accumulation was observed in the medium as the major biotransformed product along with transient formation of vanillin. A maximum amount of 400 mg/l vanillic acid accumulation was observed, when cultures were grown on 5 mM ferulic acid at 28 degrees C. This accumulation of vanillic acid was found to be stable in the culture media for a long period of time, thus facilitating its recovery. Purification of vanillic acid was achieved by gel filtration chromatography using Sephadex LH-20 matrix. Catabolic route of ferulic acid biotransformation by S. sannanensis has also been demonstrated. The metabolic inhibitor experiment [by supplementation of 3,4 methylenedioxy-cinnamic acid (MDCA), a metabolic inhibitor of phenylpropanoid enzyme 4-hydroxycinnamoyl-CoA ligase (4-CL) along with ferulic acid] suggested that biotransformation of ferulic acid into vanillic acid mainly proceeds via CoA-dependent route. In vitro conversions of ferulic acid to vanillin, vanillic acid and vanillin to vanillic acid were also demonstrated with cell extract of S. sannanensis. Further degradation of vanillic acid to other intermediates such as, protocatechuic acid and guaiacol was not observed, which was also confirmed in vitro with cell extract.

Co-production of caffeic acid and p-hydroxybenzoic acid from p-coumaric acid by Streptomyces caeruleus MTCC 6638.

In a culture medium of Streptomyces caeruleus MTCC 6638 grown with p-coumaric acid (5 mM) as the sole source of carbon, co-production of caffeic acid and p-hydroxybenzoic acid was observed. Both caffeic acid and p-hydroxybenzoic acid are important phenolic compounds with pharmaceutical importance. These biotransformed products were identified by high-performance liquid chromatography and electrospray ionization mass spectrometry. Obtained data suggest that p-coumaric acid was possibly utilized by two different routes, resulting in the formation of a hydroxycinnamate and a hydroxybenzoate compound. However, higher concentration of p-coumaric acid (10 mM) favoured caffeic acid formation. Addition of 5 mM p-coumaric acid into S. caeruleus cultures pre-grown on minimal medium with 1.0 g/l glucose resulted in the production of 65 mg/l caffeic acid. Furthermore, S. caeruleus cells were able to produce the maximum amount of caffeic acid when pre-grown on nutrient broth for 16 h. Under this condition, the addition of 5 mM p-coumaric acid was sufficient for the S. caeruleus culture to produce 150 mg/l caffeic acid, with a molar yield of 16.6% after 96 h of incubation.

An efficient isocratic separation of hydroxycinnamates and their corresponding benzoates from microbial and plant sources by HPLC.

A rapid HPLC-based separation method was developed to analyse phenolic flavour components. In the present study, ferulic acid, 4-coumaric acid, 4-hydroxybenzoic acid, 4-hydroxybenzaldehyde, vanillic acid and vanillin were chromatographed on various C(18) columns (Prodigy ODS2, Synergi Hydro-RP, Lichrosorb and Columbus). A dual-wavelength UV detector was used for the precise identification of the eluted components. An isocratic elution with aqueous trifluoroacetic acid (1 mM)/methanol (17:8) at a flow rate of 1.0 ml/min separated all the above six phenolic compounds within 21 min on a C(18) reverse-phase column (Synergi Hydro-RP) with stable baseline resolution.