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41.
Primaquine ( PQ ) is the only drug used to prevent relapse of malaria due to P. vivax and P. ovale, by eradicating the dormant liver form of the parasite (hypnozoites). The side‐effects associated with PQ limits is uses in treatment of malaria. To overcome the premature oxidative deamination and to increase the life span of drug in the biological system, the novel glyco‐conjugates of PQ were synthesized by coupling of primaquine with hexoses in phosphate buffer. The saccharide part of the hybrid molecules thought to direct the drug to the liver, where hypnozoites resides. All the synthesized compounds were fully characterized and evaluated for their radical curative activities. The three compounds viz glucoside ( 15a ), galactoside ( 15b ) and mannoside ( 15c ) with high activity were tested for their activity in rhesus monkeys where the most active compound 15b showed twofold activity (100% radical curative activity at 1.92 mmol/kg) than the standard drug PQ diphosphate (3.861 mmol/kg). It is proposed that results from these studies may be advantageous to develop a new potent tissue schizonticide antimalarial compound.  相似文献   
42.
43.
A rare species i.e. A. nidulans is reported as a causative agent of allergic fungal rhinosinusitis in this study. It is an increasingly recognized type of chronic recurring hypertrophic sinus disease. There are more than 185 species of aspergillus and over 95% of all infections are caused by A. fumigatus, A. flavus and A. niger. A. fumigatus alone accounts for the large majority of cases of both invasive and non invasive aspergillosis. A young immunocompetent lady presented with bilateral nasal obstruction due to multiple polypoid mass at Sheth Vadilal Sarabhai General Hospital, Ahmedabad. Provisional diagnosis of sinonasal polyposis possibly due to fungal cause with infiltration in to nasal cavity was made. Bilateral functional endoscopic sinus surgery with polypectomy was done. The specimen was examined by standard methods and the fungus was identified as A. nidulans by slide culture.  相似文献   
44.

Purpose

Nanoparticles (NPs) exhibiting responsiveness towards pH variations in organs, tissue microenvironments and cellular compartments can significantly add on to the drug delivery potential. Here, we have developed NPs from an amphipathic dipeptide, Arginine-α, β-dehydrophenylalanine (RΔF), and tried to explore their pH responsive drug delivery potential in various cancer cells.

Methods

RΔF-NPs were architectured by harnessing the process of molecular self-assembly followed by the assessment of effect of pH on NPs morphology using zetasizer, SEM and CD. FTIR and PXRD analysis of the dipeptide and doxorubicin (Dox) were carried out for compatibility assessment followed by encapsulation of Dox in RΔF-NPs. RΔF-Dox-NPs were evaluated for pH dependent release as well as for in-vitro cellular internalization and efficacy in cancer cells.

Results

RΔF self-assembled to form monodispersed particles at pH 7. SEM analysis revealed a loss of overall particle morphology along with particle aggregation at highly acidic and basic pH respectively. The NPs demonstrated a slow and sustained release behaviour at pH 7 (97.64?±?4.71% after 36 h) in comparison to pH 2 (90.27?±?1.45% after 8 h) and pH 10 (96.39?±?3.87% after 12 h). In-vitro efficacy studies carried-out in various cancer cells revealed that RΔF-Dox-NPs exhibited higher efficacy with 1.65, 1.95 and 13.34 fold lower IC50 values in comparison to Dox in C6, HCT-116 and AGS cell lines.

Conclusions

RΔF-Dox-NPs with higher drug release at acidic pH, enhanced internalization in cancer cells along with higher cytotoxic potential can act as effective pH responsive drug delivery systems.
  相似文献   
45.
Present communication reports the effects of environmentally available, low doses of tetra chloro di benzo-p-dioxin (2,3,7,8 TCDD) to lysosomal enzymes in mice liver. The study tests the hypothesis, in vivo exposure of low dose TCDD provokes dose and duration dependent toxic effects to key lysosomal enzymes and thereby causes cellular apoptotic changes. Three groups of female Swiss albino mice were subjected to two doses of TCDD (0.004 mg/kg bw/d, 0.04 mg/kg bw/d) for 2, 4 and 6 days of exposure durations. The results indicated significant exposure duration dependent effects of TCDD in mice liver cells. The results suggested that TCDD possibly induced an increase in intracellular ions or ROS which in turn altered different physiological activities by affecting different metabolic pathway of the liver cells. The altered functions of key lysosomal enzymes by TCDD may also evoke the process of cellular apoptosis.  相似文献   
46.

Context:

Cirrhosis of liver is an important cause of morbidity and mortality and if associated with peripheral neuropathy (PN) it also poses a huge financial, psychological burden for the patients and their families.

Aim:

The aim of the present study was to study the magnitude of PN among subjects with cirrhosis of liver presenting to tertiary care teaching hospital in central rural India.

Settings and Design:

A cross-sectional study was performed in a tertiary care teaching hospital.

Materials and Methods:

In all patients of cirrhosis of liver irrespective of etiology, aged 15 and above, undergone clinical assessment for peripheral nervous systems damage and confirmed by nerve conduction studies.

Statistical Analysis Used:

We used chi square test to study associations. P value ≤0.05 was considered as significant. Crude odds ratios were computed to assess the strength of association between independent variables and dependent variables along with their 95% confidence intervals.

Results:

We included 207 of cirrhosis of liver patients admitted in medicine department from November 2010 through November 2013. Nearly 83% patients were male and 63.2% patients were under the age of 45 years. Common features in these patients were ascites (71%) splenomegaly (63.3%) pedal edema (61.4%) icterus (46.4%) tingling (44.9%) gastrointestinal bleeding(39.1%), ataxia (26.6%), numbness(26.6%), distal motor weakness (21.7%) and paresthesia(20.8%). Among the manifestation of peripheral nerve involvement, loss of ankle reflex was the most common feature in 51.7%, followed by loss of temperature sense 29.5%, loss of vibration sense 20.8%, loss of touch 16.4%, loss of position sense 14.5% and loss of pain in 6.3% of the patients. Peripheral neuropathy was found in 53.6% [95% CI: 46.58- 60.56] study subjects on electrophysiological study.

Conclusions:

Analysis of electrophysiological study shows that the PN is very common in study subjects with cirrhosis of liver, especially in male subjects, during the middle age group.  相似文献   
47.
SARS-CoV-2 (Severe Acute Respiratory Syndrome-Coronavirus 2) has accumulated multiple mutations during its global circulation. Recently, three SARS-CoV-2 lineages, B.1.1.7 (501Y.V1), B.1.351 (501Y.V2) and B.1.1.28.1 (P.1), have emerged in the United Kingdom, South Africa and Brazil, respectively. Here, we have presented global viewpoint on implications of emerging SARS-CoV-2 variants based on structural–function impact of crucial mutations occurring in its spike (S), ORF8 and nucleocapsid (N) proteins. While the N501Y mutation was observed in all three lineages, the 501Y.V1 and P.1 accumulated a different set of mutations in the S protein. The missense mutational effects were predicted through a COVID-19 dedicated resource followed by atomistic molecular dynamics simulations. Current findings indicate that some mutations in the S protein might lead to higher affinity with host receptors and resistance against antibodies, but not all are due to different antibody binding (epitope) regions. Mutations may, however, result in diagnostic tests failures and possible interference with binding of newly identified anti-viral candidates against SARS-CoV-2, likely necessitating roll out of recurring “flu-like shots” annually for tackling COVID-19. The functional relevance of these mutations has been described in terms of modulation of host tropism, antibody resistance, diagnostic sensitivity and therapeutic candidates. Besides global economic losses, post-vaccine reinfections with emerging variants can have significant clinical, therapeutic and public health impacts.  相似文献   
48.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Artemisia maritima L., a potent source of Santonin (a drug used to expel roundworms), forms isolated...  相似文献   
49.
50.
There was a wide range of activity and chlamydial diagnoses between the 177 clinics that responded. Most (92%) clinics have nucleic acid tests for chlamydial diagnosis. Different practitioners largely share roles in providing advice to patients about partner notification, treatment adherence, safer sex advice and abstinence. Most (97%) clinics have information leaflets about chlamydia, although about 30% of clinics lack leaflets containing information about antibiotics and hormonal contraception. About two-third clinics follow the National Guideline recommended interval for providing a test of cure where this is indicated. Only 18% of clinics routinely ask patients to reattend, with 40% having a policy of no routine follow-up and 62% using telephone or text follow-up. These categories were not mutually exclusive. Most (86%) of the 146 English clinics had a local Chlamydia Screening Programme coordinator for their Primary Care Trust area, although cooperation varies, with cooperation over treatment of 70% and Programme policy of 62%.  相似文献   
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