Gut feelings: the relations between depression, anxiety, psychotropic drugs and the gut microbiome.

The gut microbiome is involved in the bi-directional relationship of the gut - brain axis. As most studies of this relationship are small and do not account for use of psychotropic drugs (PTDs), we explored the relations of the gut microbiome with several internalizing disorders, while adjusting for PTDs and other relevant medications, in 7,656 Lifelines participants from the Northern Netherlands (5,522 controls and 491 participants with at least one internalizing disorder). Disorders included dysthymia, major depressive disorder (MDD), any depressive disorder (AnyDep: dysthymia or MDD), generalized anxiety disorder (GAD) and any anxiety disorder (AnyAnx: GAD, social phobia and panic disorder). Compared to controls, 17 species were associated with depressive disorders and 3 were associated with anxiety disorders. Around 90% of these associations remained significant (FDR <0.05) after adjustment for PTD use, suggesting that the disorders, not PTD use, drove these associations. Negative associations were observed for the butyrate-producing bacteria Ruminococcus bromii in participants with AnyDep and for Bifidobacterium bifidum in AnyAnx participants, along with many others. Tryptophan and glutamate synthesis modules and the 3,4-Dihydroxyphenylacetic acid synthesis module (related to dopamine metabolism) were negatively associated with MDD and/or dysthymia. After additional adjustment for functional gastrointestinal disorders and irritable bowel syndrome, these relations remained either statistically (FDR <0.05) or nominally (P < 0.05) significant. Overall, multiple bacterial species and functional modules were associated with internalizing disorders, including gut - brain relevant components, while associations to PTD use were moderate. These findings suggest that internalizing disorders rather than PTDs are associated with gut microbiome differences relative to controls.

Environmental factors shaping the gut microbiome in a Dutch population.

The gut microbiome is associated with diverse diseases1-3, but a universal signature of a healthy or unhealthy microbiome has not been identified, and there is a need to understand how genetics, exposome, lifestyle and diet shape the microbiome in health and disease. Here we profiled bacterial composition, function, antibiotic resistance and virulence factors in the gut microbiomes of 8,208 Dutch individuals from a three-generational cohort comprising 2,756 families. We correlated these to 241 host and environmental factors, including physical and mental health, use of medication, diet, socioeconomic factors and childhood and current exposome. We identify that the microbiome is shaped primarily by the environment and cohabitation. Only around 6.6% of taxa are heritable, whereas the variance of around 48.6% of taxa is significantly explained by cohabitation. By identifying 2,856 associations between the microbiome and health, we find that seemingly unrelated diseases share a common microbiome signature that is independent of comorbidities. Furthermore, we identify 7,519 associations between microbiome features and diet, socioeconomics and early life and current exposome, with numerous early-life and current factors being significantly associated with microbiome function and composition. Overall, this study provides a comprehensive overview of gut microbiome and the underlying impact of heritability and exposures that will facilitate future development of microbiome-targeted therapies.

Enhanced photocatalytic activity, transport properties and electronic structure of Mn doped GdFeO3 synthesized using the sol-gel process.

In this work we have synthesized Mn doped GdFeO3 nano-particles using a green and facile sol gel method and studied their photocatalytic, optical, vibrational and electrical properties. The Rietveld refinement of the XRD profiles suggests that all the materials have an orthorhombic Pbnm crystal structure. The transmission electron microscope (TEM) images show the decrease of the average particle size from 140 to 80 nm with the Mn concentration. The high crystallinity of the synthesized particles is confirmed from the HR-TEM images. Raman spectrum is employed to investigate the phonon modes of the materials. The optical band gap of the materials is obtained from the UV-vis reflectance spectroscopy (DRS) using Tauc relation which indicates the reduction of the band gap from 2.18 to 1.72 eV with Mn-doping. The photocatalytic activity of the materials is studied by the photocatalytic degradation of rhodamine B (Rh-B) in aqueous solution under visible light illumination. The substitution of Mn at the Fe site introduces an extra electronic state between the conduction band and the valence band which reduces the electronic band gap and enhances the Rh-B degradation efficiency. A 30% Mn doping at the Fe site (GFMO3) provides an optimum space charge width which assists to attain the maximum rate of degradation of the Rh-B dye. The doping of Mn3+ reduces the photogenerated electron and hole recombination rate and hence more charge carriers take part in the redox reaction which facilitates the photo-catalytic efficiency in GFMO3. The degradation rate enhances by a factor of 2.5 for GFMO3 as compared to pure GdFeO3. The highest photocurrent density of 1.31 µA cm-2 of GFMO3 with respect to other materials promotes the separation and transfer of the photo generated charge carriers. The possible photocatalytic mechanism of the Mn doped GdFeO3 is also critically discussed. Alternating current impedance spectroscopy is used to study the electrical properties of the synthesized materials. The increase in the conductivity with the Mn concentration is explained on the basis of the band gap reduction and this is consistent with the Smit and Wijn theory. Magnetic measurement is performed to measure the magnetization strength which is useful to separate the photocatalyst by simply using a magnet. The temperature dependent magnetization measurement suggests the anti-ferromagnetic (AFM) behaviour of the studied materials with the decrease of Néel temperature (TN) with Mn concentration. The XPS study reveals the presence of multiple oxidation states of Fe(2+/3+) and Mn(4+/3+) in these materials which facilitates the conductivity as well as the oxidation/reduction efficiency at the surface of the catalyst. The band gap reduction and its effect on the enhancement of the photocatalytic degradation efficiency with Mn doping are also discussed from the density of states calculations. Thus, this study describes a promising approach for the organic pollutant degradation by designing an efficient and stable perovskite photocatalyst.

Infrared tunable, two colour-band photodetectors on flexible platforms using 0D/2D PbS-MoS2 hybrids.

Two-dimensional (2D) MoS2 nanosheets have been integrated with zero-dimensional (0D) PbS quantum dots to achieve a superior optical response extending to the short-wavelength infrared region along with a broadband visible response for multispectral photodetection. The 0D/2D hybrid nanostructures have been synthesized by a one pot, stabilizer-free solvothermal growth process. Microscopic and spectroscopic studies confirmed the formation of PbS QD decorated semiconducting 2H-MoS2 layers. The size tunable absorption features with longer photo-generated carrier lifetime of synthesized hybrid nanostructures indicate that the integration of PbS QDs in MoS2 could be a viable approach for fabricating two-colour band photodetectors, viz. visible broadband and wavelength selective short-wave IR photodetectors. Devices have also been demonstrated on polyethylene terephthalate substrates using a solution-based synthesis technique for flexible and ultrathin optoelectronic device applications. The photodetection performance of fabricated devices suggests that the synergic 0D/2D hybrid nanostructures are significantly superior to solution processed hybrid devices operating in the infrared region. The successful integration of 0D QDs in 2D materials may pave the way for novel, high performance, next-generation CMOS compatible flexible photonic devices.

Synergistic effect of polymer encapsulated silver nanoparticle doped WS2 sheets for plasmon enhanced 2D/3D heterojunction photodetectors.

Chemical doping and plasmonic enhanced photoresponsivity of two dimensional (2D) n-WS2/p-Si heterojunctions are demonstrated for the first time. Novel PVP coated Ag0 intercalation induced synthesis has led to the formation of impurity-free, chemically doped few-layer n-WS2 with reversed conductivity following the Maxwell-Wagner-Sillars interfacial effect. The resultant composite film exhibits excellent stability and tunable plasmonic absorption due to silver nanoparticles of different sizes. A sharp band-edge absorption of the hybrid material indicates the presence of spin-orbit coupled direct band gap transitions in WS2 layers, in addition to a broader plasmonic peak attributed to Ag nanoparticles. Stabilized Ag-nanoparticle (∼4-6 nm) embedded electron rich n-WS2 has been used to fabricate plasmon enhanced, silicon compatible heterojunction photodetectors. The detectors exhibited superior properties, possessing a photo-to-dark current ratio of ∼103, a very high responsivity (8.0 A W-1) and an EQE of 2000% under 10 V bias with a broad spectral photoresponse in the wavelength range of 400-1100 nm. The results provide a new paradigm for intercalant impurity-free metal nanoparticle assisted exfoliation of n-type few-layer WS2, with the nanoparticles playing a dual role towards the realization of 2D materials based broadband heterojunction optoelectronic devices by inducing chemical doping as well as tunable plasmon enhanced absorption.

Dielectric Relaxation of NiFe2O4/Gd2O3 Core-Shell Nanoparticles.

Gd2O3 encapsulated NiFe2O4 core-shell nano-particles (CSNPs) have been synthesized by chemical route. The phase formation of the materials is confirmed by X-ray diffraction analysis. The average particle size is found to be 60 nm by transmission electron microscope. The band gap of NiFe2O4/Gd2O3 CSNPs is obtained by UV-visible absorption spectroscopy. The observed band gap of 4.38 eV lies in between the individual band gap of Gd2O3 and NiFe2O4. The frequency-dependent dielectric relaxation of the material is investigated in the temperature range from 303 K to 543 K. The temperature dependent relaxation times are found to obey Arrhenius law having activation energy of 0.3 eV. The Nyquist plots of impedance data are analyzed by the RC equivalent circuit having a constant phase element. The dielectric relaxation is modelled by Havriliak-Negami technique in the electric modulus formalism. The frequency dependent conductivity spectra follow the double power law.

Predictors of weight loss during conformal radiotherapy for head and neck cancers - how important are planning target volumes?

AIMS: Nutritional compromise is common during high dose radiotherapy (RT) or chemoradiotherapy (CRT) for head and neck cancers. We aimed to identify the factors that determine nutritional outcome for head and neck cancer patients during radiotherapy. METHODS: Data from 103 patients with head and neck cancer treated with highly conformal radiotherapy to doses of 60 Gy or more in 30-33 fractions in the adjuvant or definitive setting was analyzed. All patients received complex 3D conformal radiotherapy (3DCRT) or intensity modulated radiotherapy (IMRT). Patients received regular nutritional counseling and need-based interventions. Their weight was recorded at the beginning and end of radiotherapy. Using univariate and multivariate models we tested possible predictors of weight loss of >5% and NG tube requirement. RESULTS: The mean weight loss was 3.8%. The incidence of weight loss >5% was 37.9% and NG tube placement was 24.3%. The factors significantly associated with >5% weight loss in the univariate analysis were tumor site (oro-hypopharyngeal vs. others), definitive vs. adjuvant RT; prescription dose of >60 Gy vs. 60 Gy; CRT vs. RT alone; prescription dose planning target volume (PTV) volume >235 cc and total PTV volume >615 cc. Age, sex, T stage, N stage and modality (3DCRT/IMRT) were not significant. In multivariate analysis, the total PTV volume, prescription dose PTV volume and use of chemotherapy were significant after controlling for other factors. Patients could be risk stratified based on the use of CRT and large PTV volumes. Patients with none, one or both factors had a likelihood of >5% weight loss of 0%, 30.3%, and 56.9% (p < 0.001) and likelihood of NG tube placement of 5.3%, 15.2% and 37.3% (p = 0.007). CONCLUSIONS: It is possible to predict weight loss and NG tube requirements from disease and treatment related factors. PTV volumes are important predictors of nutritional compromise. Risk stratification may enable more focused counseling and identification of patients who require preventive interventions.

Isolation and characterization of Pseudomonas sp. STM 997 from soil sample having potentiality to degrade 3,6-dimethyl-1-keto-1,2,3,4-tetrahydrocarbazole: a novel approach.

A pure colony of a bacterium from contaminated soil was isolated by exploiting 3,6-dimethyl-1-keto-1,2,3,4-tetrahydrocarbazole, a novel carbazole derivative, having indole moiety as well as 3-methyl functionality both in aromatic and hydro-aromatic moiety, as a sole source of carbon and energy. Taxonomical studies, biochemical analysis, and 16S rDNA sequence analysis indicated that the isolated strain has close similarity with Pseudomonas sp. Thin-layer chromatography followed by HPLC and mass spectroscopic study indicates that the isolated Pseudomonas sp. STM 997 degrades 3,6-dimethyl-1-keto-1,2,3,4-tetrahydrocarbazole, and this strain may be useful in the bioremediation of environments contaminated by the compounds containing carbazole moiety with methyl substituents at various reactive sites. This study also provides an evidence in favor of the suggested biodegradation of 3-methylcarbazole to carbazole in plants.

Renal transplant in a child with Bardet-Biedl syndrome: A rare cause of end-stage renal disease.

Bardet-Biedl syndrome (BBS) is a rare cause of renal failure requiring renal replacement therapy. It is an autosomal recessive condition characterized by retinitis pigmentosa, postaxial polydactyly, central obesity, mental retardation, hypogonadism, and renal involvement. We report the first successful renal transplant in a case of BBS from India.

Development of a respiratory virus panel test for detection of twenty human respiratory viruses by use of multiplex PCR and a fluid microbead-based assay.

Virology laboratories historically have used direct fluorescent-antibody assay (DFA) and culture to detect six or seven respiratory viruses. Following the discovery of five new human respiratory viruses since 2000, there is an increasing need for diagnostic tests to detect these emerging viruses. We have developed a new test that can detect 20 different respiratory virus types/subtypes in a single 5-h test. The assay employs multiplex PCR using 14 virus-specific primer pairs, followed by a multiplexed target-specific primer extension (TSPE) reaction using 21 primers for specific respiratory virus types and subtypes. TSPE products were sorted and identified by using a fluid microsphere-based array (Universal Array; TmBioscience Corporation, Toronto, Canada) and the Luminex x-MAP system. The assay detected influenza A and B viruses; influenza A virus subtypes H1, H3, and H5 (including subtype H5N1 of the Asian lineage); parainfluenza virus types 1, 2, 3, and 4; respiratory syncytial virus types A and B; adenovirus; metapneumovirus; rhinovirus; enterovirus; and coronaviruses OC43, 229E, severe acute respiratory syndrome coronavirus, NL63, and HKU1. In a prospective evaluation using 294 nasopharyngeal swab specimens, DFA/culture detected 119 positives and the respiratory virus panel (RVP) test detected 112 positives, for a sensitivity of 97%. The RVP test detected an additional 61 positive specimens that either were not detected by DFA/culture or were positive for viruses not tested for by DFA/culture. After resolution of discordant results by using a second unique PCR assay and by using a combined reference standard of positivity, the RVP test detected 180 of 183 true positives, for a sensitivity of 98.5%, whereas DFA and culture detected only 126 of 183 true positives, for a sensitivity of 68.8%. The RVP test should improve the capabilities of hospital and public health laboratories for diagnosing viral respiratory tract infections and should assist public health agencies in identifying etiologic agents in respiratory tract infection outbreaks.

Renal Transplantation - An Experience of 500 Patients.

BACKGROUND: Renal transplantation is the treatment modality of choice for patients with end stage kidney failure. We present our experience of graft and patient survival of initial 500 renal transplants performed between May 1991 and July 2006, at Army Hospital (R&R). MATERIAL AND METHODS: All patients received triple drug immunosuppression with cyclosporine/tacrolimus, azathioprine/ mycophenolate mofetil and steroids. Patients in high risk group received induction therapy with IL-2 receptor blockers/anti-thymocyte globulin. RESULTS: Majority of the recipients (79%) were males, whereas majority of the donors (59.4%) were females. In the donor profile, 385 (77%) transplants were live related, 108 (21.6 %) were spousal and 7 (1.4%) were cadaveric transplants. Mean age of the donors and recipients was 42.11 ± 11.53 years (range 19-72 years) and 33 ± 9.39 years (range 5-60 years) respectively. Eighty two patients (16.4%) were lost to follow up and the present data on rejections, patients and graft survival pertains to 418 patients. These patients have been followed up for a mean period of 2.63 years (SE, 0.122; median 1.8 years; range 0-13.36 years). Acute rejection episodes occurred in 115 (27.3%) patients and 95% of these could be reversed with steroids/ATG. Sixty eight patients (16%) have died on follow-up. Our one-year, 5 year and 10 year estimated graft survival is 95.4% (SE, 0.01), 80.5% (SE, 0.03) and 53.1% (SE, 0.09) respectively and patient survival at one year is 93.2% (SE, 0.01). The estimated graft and patient survival in our series is 9.83 (95% CI, 8.92-10.73) and 9.80 (8.93-10.67) years respectively. CONCLUSION: This centre's short-term graft survival of 95.4% is comparable to the best centres of the world.

A prototype ultrasound-guided laparoscopic radiofrequency ablation system.

BACKGROUND: Advanced laparoscopic procedures, particularly laparoscopic liver resection and ablation, may benefit from image-guided surgery techniques that involve interactive three-dimensional imaging and instrument tracking. METHODS: A prototype system for laparoscopic ultrasound-guided radiofrequency ablation was designed and implemented. This system uses an infrared camera to track instruments and runs on a personal computer. Features of the system include spatially registered ultrasound visualization, volume reconstruction, and interactive targeting. Targeting of accuracy studies was performed by directing a tracked needle to a phantom target. RESULTS: Ultrasound data collection and volume reconstruction can be achieved within minutes and interactively reviewed by the surgeon. Early results with phantom experiments demonstrate a targeting accuracy of 5 to 10 mm. CONCLUSIONS: These results support the further development of this and similar image-guided surgery systems for specific laparoscopic procedures. Eventually, rigorous clinical evaluation will be necessary to prove their value.

Intravesical Explosion during Transurethral Resection of Prostate - a reminder.

Intravesical explosion during transurethral resection of the prostate (TURP) is an extremely rare but dreaded complication and results in rupture of the bladder. It is believed that intravesical explosion occurs due to formation of explosive gases in the bladder during TURP and its admixture with air. A case of intravesical explosion during TURP resulting in bladder rupture at our institution is described. Though the management of this catastrophe is relatively straightforward, it has the potential for dire consequences. We emphasize that, despite its rare occurrence, it is preventable and suggest measures to avoid it.

A Comparative Study of Laparoscopic with Conventional Open Donor Nephrectomy in Renal Transplantation.

BACKGROUND: Laparoscopic donor nephrectomy (LDN) has been gaining popularity among kidney donors. There have been concerns about the safety and efficacy of the procedure as compared to open donor nephrectomy (ODN). We compare our results on LDN with ODN. METHODS: We retrospectively analysed our data of LDN and ODN. Duration of surgery, blood loss, period of hospitalisation, per oral intake and analgesic requirements. RESULT: 22 LDNs were done, the operation time ranged from 220-300 minutes, and blood loss from 100-150ml. In the first 10 laparoscopic operations four cases required conversion to open surgical dissection. Only one case was converted to open surgery in the subsequent 12 laparoscopic cases. Oral intake was started on the first postoperative day. Analgesic requirement in laparoscopy cases was less. Patients were mobilised on the first day after surgery. Patients were discharged by seventh day. There was no significant difference in the functioning of the graft after revascularisation in the recipient. CONCLUSION: Laparoscopic donor nephrectomy is a safe and effective technique of donor nephrectomy.

The joint contributions of saccades and ocular drift to repeated ocular fixations.

We measured the joint contributions of different sized saccades and ocular drift to overall performance in an alternating fixation task. Subjects repeatedly shifted fixation between the centres of a pair of bars of width 2 degrees -2 arc min, either mentally selected or electronically cut from a stationary sine grating display. Eye movement patterns exhibited consistent features across all displays, and pairs of widely separated bars were studied most. Variability (S.D.) and relative accuracy (under/overshooting bias) were estimated from the concentration of eye positions over the two target bars. Overall variability, i.e. for eye movements as a whole, reached a minimum of 5 min for bar widths less than 20 min across subjects, displays and tasks. This was consistent, as were several other aspects of the study, with a constant 20-min diameter goal zone hypothesis. For wide bars, overall variability increased nearly as the square root of bar width, and for narrow bars, was independent of bar separation. A typical between-bar crossing saccade was tightly constrained in departure point but widely scattered in landing position, the associated variability increasing with bar separation. The final high overall precision was achieved largely by within-bar saccades of greater than 7.5 min effective amplitude that were present at a rate of 1 (range 0.3-3) per crossing saccade. This is consistent with views that very small saccades (the smaller microsaccades) make little obvious contribution to oculomotor performance.

High-level resistance to 3'-azido-3'-deoxythimidine due to a deletion in the reverse transcriptase gene of human immunodeficiency virus type 1.

A variant of human immunodeficiency virus type 1 (HIV-1) possessing a deletion in the reverse transcriptase (RT) gene at codon 67 was identified in a patient who had failed combination antiretroviral therapy. This deletion initially emerged under the selective pressure of combination therapy with 3'-azido-3'-deoxythymidine (AZT) plus 2',3'-dideoxyinosine. It has persisted for more than 3 years in association with the accumulation of a variety of other well-described drug resistance mutations and an uncharacterized mutation at RT codon 69 (T69G). Phenotypic studies demonstrated that the codon 67 deletion by itself had little effect on AZT sensitivity. However, in the context of the T69G mutation and three other mutations known to be associated with AZT resistance (K70R, T215F, and K219Q), this deletion led to a increase in AZT resistance from 8. 5-fold to 445-fold. A further increase in resistance (up to 1, 813-fold) was observed when two mutations associated with nonnucleoside RT inhibitor resistance (K103N and L74I) were added to the deletion T69G K70R T215F K219Q construct. Hence, these results establish that a deletion at RT codon 67 may be selected for in the presence of antiretroviral therapy and may lead to high-level resistance to AZT.

Unilateral pellucid marginal degeneration.

Pellucid marginal degeneration (PMD) is a rare and usually a bilateral condition. We report a case of typical PMD with a unilateral presentation.