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1.
An efficient protocol for in-vitro propagation of an important ornamental crop, Petunia hybrida Vilm. Cv. “Bravo” was developed. The explants that were used to carry out the experiment were Leaf segments, nodal segments and shoot tips. Nodal segments recorded highest per cent asepsis followed by shoot tips and leaf segments. Asepsis was found to be highest when the explants were sterilized with Fungicide (Carbendazim) 0.02% for the duration of 30 min followed by 0.1% HgCl2 for duration of 10 min and then ethanol 70% for 10 s. Longer duration of the sterilant treatment showed more necrotic effects on the explants, thus mercuric chloride treatment when given for 5 min proved to be more effective in terms of survival of the explants. Maximum establishment per cent was recorded in Murashige and Skoog (MS) media fortified with BAP (1.5 mg L−1) and IBA (0.5 mg L−1) in shoot tips and nodal segments, i.e. 97.90 and 95.74% respectively. Callus was efficiently induced and developed when PGR amalgamation of BAP (0.1 mg L−1) and 2,4-D (1.5mg L−1) was used. Kinetin at the concentration of 2.0 mg L−1 along with IBA at 0.5mg L−1 recorded highest callus regeneration in both leaf and internodal segment derived callus. Maximum proliferation percent of shoots (97.90%), highest number of shoots (20.50 explant−1) and maximum length of shoot (2.70 cm) was recorded in PGR combination of IBA and BAP both at 0.5 mg L1 concentration level. Rhizogenesis was recorded to be highest in the MS media containing IBA 1.00 mg L−1. Best hardening media which recorded maximum survival per cent 92.50% was noticed on the media formulation comprised of equal ratio of perlite and vermiculite mix, under poly house conditions.  相似文献   
2.
Exome sequencing coupled with homozygosity mapping was used to identify a transition mutation (c.794T>C; p.Leu265Ser) in ELMOD3 at the DFNB88 locus that is associated with nonsyndromic deafness in a large Pakistani family, PKDF468. The affected individuals of this family exhibited pre-lingual, severe-to-profound degrees of mixed hearing loss. ELMOD3 belongs to the engulfment and cell motility (ELMO) family, which consists of six paralogs in mammals. Several members of the ELMO family have been shown to regulate a subset of GTPases within the Ras superfamily. However, ELMOD3 is a largely uncharacterized protein that has no previously known biochemical activities. We found that in rodents, within the sensory epithelia of the inner ear, ELMOD3 appears most pronounced in the stereocilia of cochlear hair cells. Fluorescently tagged ELMOD3 co-localized with the actin cytoskeleton in MDCK cells and actin-based microvilli of LLC-PK1-CL4 epithelial cells. The p.Leu265Ser mutation in the ELMO domain impaired each of these activities. Super-resolution imaging revealed instances of close association of ELMOD3 with actin at the plasma membrane of MDCK cells. Furthermore, recombinant human GST-ELMOD3 exhibited GTPase activating protein (GAP) activity against the Arl2 GTPase, which was completely abolished by the p.Leu265Ser mutation. Collectively, our data provide the first insights into the expression and biochemical properties of ELMOD3 and highlight its functional links to sound perception and actin cytoskeleton.  相似文献   
3.
Insect flight is regulated by various sensory inputs and neuromodulatory circuits which function in synchrony to control and fine-tune the final behavioral outcome. The cellular and molecular bases of flight neuromodulatory circuits are not well defined. In Drosophila melanogaster, it is known that neuronal IP3 receptor mediated Ca2+ signaling and store-operated Ca2+ entry (SOCE) are required for air-puff stimulated adult flight. However, G-protein coupled receptors (GPCRs) that activate intracellular Ca2+ signaling in the context of flight are unknown in Drosophila. We performed a genetic RNAi screen to identify GPCRs that regulate flight by activating the IP3 receptor. Among the 108 GPCRs screened, we discovered 5 IP3/Ca2+ linked GPCRs that are necessary for maintenance of air-puff stimulated flight. Analysis of their temporal requirement established that while some GPCRs are required only during flight circuit development, others are required both in pupal development as well as during adult flight. Interestingly, our study identified the Pigment Dispersing Factor Receptor (PdfR) as a regulator of flight circuit development and as a modulator of acute flight. From the analysis of PdfR expressing neurons relevant for flight and its well-defined roles in other behavioral paradigms, we propose that PdfR signaling functions systemically to integrate multiple sensory inputs and modulate downstream motor behavior.  相似文献   
4.
Mughees  Mohd  Chugh  Himanshu  Wajid  Saima 《Protoplasma》2020,257(2):345-352
Protoplasma - Vesicular trafficking between endoplasmic reticulum and Golgi plays a major role in the growth and proliferation of breast cancer cells. Various proteins regulate this ER-Golgi...  相似文献   
5.
Haider  Saida  Sajid  Irfan  Batool  Zehra  Madiha  Syeda  Sadir  Sadia  Kamil  Noor  Liaquat  Laraib  Ahmad  Saara  Tabassum  Saiqa  Khaliq  Saima 《Neurochemical research》2020,45(11):2762-2774

Noise has always been an important environmental factor that induces health problems in the general population. Due to ever increasing noise pollution, humans are facing multiple auditory and non-auditory problems including neuropsychiatric disorders. In modern day life it is impossible to avoid noise due to the rapid industrialization of society. Continuous exposure to noise stress creates a disturbance in brain function which may lead to memory disorder. Therefore, it is necessary to find preventive measures to reduce the deleterious effects of noise exposure. Supplementation of taurine, a semi essential amino acid, is reported to alleviate psychiatric disorders. In this study noise-exposed (100 db; 3 h daily for 15 days) rats were supplemented with taurine at a dose of 100 mg/kg for 15 days. Spatial and recognition memory was assessed using the Morris water maze and novel object recognition task, respectively. Results of this study showed a reversal of noise-induced memory impairment in rats. The derangements of catecholaminergic and serotonergic levels in the hippocampus and altered brain antioxidant enzyme activity due to noise exposure were also restored by taurine administration. This study highlights the importance of taurine supplementation to mitigate noise-induced impaired memory via normalizing the neurochemical functions and reducing oxidative stress in rat brain.

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6.
Abstract

Acinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al2O3 NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10?nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al2O3 NPs ranged between 125 and 1,000?µg ml?1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al2O3 NPs up to a concentrations of 120?µg ml?1 in HeLa cell lines. These results demonstrate an effective and safer use of Al2O3 NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production.  相似文献   
7.
The liver is considered a radiosensitive organ. However, in rats, high single-dose irradiation (HDI) showed only mild effects. Consequences of fractionated irradiation (FI) in such an animal model have not been studied so far. Rats were exposed to selective liver FI (total dose 60 Gy, 2 Gy/day) or HDI (25 Gy) and were killed three months after the end of irradiation. To study acute effects, HDI-treated rats were additionally killed at several time points between 1 and 48 h. Three months after irradiation, no differences between FI and HDI treatment were found for macroscopically detectable small “scars” on the liver surface and for an increased number of neutrophil granulocytes distributed in the portal fields and through the liver parenchyma. As well, no changes in HE-stained tissues or clear signs of fibrosis were found around the portal vessels. Differences were seen for the number of bile ducts being increased in FI- but not in HDI-treated livers. Serum levels indicative of liver damage were determined for alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (γGT) and lactate dehydrogenase (LDH). A significant increase of AP was detected only after FI while HDI led to the significant increases of AST and LDH serum levels. By performing RT-PCR, we detected up-regulation of matrix metalloproteinases, MMP-2, MMP-9, MMP-14, and of their inhibitors, TIMP-1, TIMP-2 and TIMP-3, shortly after HDI, but not at 3 month after FI or HDI. Overall, we saw punctual differences after FI and HDI, and a diffuse formation of small scars at the liver surface. Lack of “provisional clot”-formation and absence of recruitment of mononuclear phagocytes could be one explanation for scar formation as incomplete repair response to irradiation.  相似文献   
8.
The DFNB79 locus harbors TPRN mutations in which have been reported in a few families with deafness. Four frameshift mutations in TPRN have been described to cause severe or severe-to-profound hearing loss in Moroccan and Pakistani families, and a single frameshift mutation was associated with progressive hearing loss in deaf individuals in a Dutch family. We identified a Pakistani family in which the affected individuals were homozygous for a pathogenic mutation, c.42_52del11, in TPRN (p.G15Afs150X). In contrast to the previously reported individuals affected by the same mutation, hearing loss is likely to be progressive in this family. Thus the same mutation of TPRN can be associated with different thresholds of hearing as well as differences in the stability of the phenotype.  相似文献   
9.

Background

Hepatitis C virus (HCV) is a major cause of liver cirrhosis and hepatocellular carcinoma and infects about 3% world population. Response to interferon therapy depends upon the genotype of the virus and factors associated with the host. Despite a good response to interferon therapy, a considerable number of genotype 3a infected patients remains unalleviated.

Results

In total forty-nine patients including twenty-five non-responders (non-SVR) and twenty-four responders (SVR) were recruited. Patients were tested for viral status at different intervals and the isolated RNA was sequenced for the NS5A region in both groups. The comparison of PKRBD of HCV between the SVR and non-SVR patients did not confirm any significant difference in the number of mutations. However, when the sequence downstream to the PKRBD of NS5A was compared, two important statistically significant mutations were observed; at positions 2309 (Ala to Ser) and 2326 (Gly to Ala). These mutations were then analysed for tertiary protein structure and important structural changes were observed. Statistically significant difference was also observed when age groups of patients were compared; younger patients showed better response than the older ones.

Conclusions

The region between PKRBD and IRRDR may be important for prediction of response to IFN therapy for genotype 3a. ISDR and PKRBD have not shown any involvement in treatment response. Further functional analyses of these findings can help in understanding the involvement of the NS5A region in interferon treatment of HCV-3a infected patients.
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10.

Background

Pakistan’s Maternal, Newborn and Child Health (MNCH) Program is faced with multiple challenges in service delivery, financial and logistic management, training and deployment of human resources, and integration within the existing health system. There is a lack of evidence on managerial aspects of the MNCH program management and implementation.

Methods and Findings

This study used qualitative methods to explore the challenges national, provincial and district program managers have faced in implementing a community midwifery program in province of Punjab while also exploring future directions for the program under a devolved health system. While the program had been designed in earnest, the planning lacked critical elements of involving relevant stakeholders in design and implementation, socio-demographic context and capacity of the existing health system. Financial limitations, weak leadership and lack of a political commitment to the problem of maternal health have also had an impact on program implementation.

Conclusions

Our study results suggest that there is a need to re-structure the program while ensuring sustainability and collaboration within the health sector to increase uptake of skilled birth attendance and improve maternal health care in Pakistan.  相似文献   
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