Design and Development of Mycobacterium tuberculosis Lysine ɛ‐Aminotransferase Inhibitors for Latent Tuberculosis Infection

Lysine ?‐aminotransferase (LAT) is a protein involved in lysine catabolism, and it plays a significant role during the persistent/latent phase of Mycobacterium tuberculosis (MTB), as observed by its up‐regulation by ~40‐fold during this stage. We have used the crystal structure of MTB LAT in external aldimine form in complex with its substrate lysine as a template to design and identify seven lead compounds with IC₅₀ ranging from 18.06 to > 90 μm . We have synthesized 21 compounds based on the identified lead, and compound 21 [2,2′‐oxybis(N′‐(4‐fluorobenzylidene)acetohydrazide)] was found to be the most active with MTB LAT IC₅₀ of 0.81 ± 0.03 μm . Compound 21 also showed a 2.3 log reduction in the nutrient‐starved MTB model and was more potent than standard isoniazid and rifampicin at the same dose level of 10 μg/mL.     

Evaluation of rk39 immunochromatographic test with urine for diagnosis of visceral leishmaniasis

This study evaluates commercially available rK39 immunochromatographic strips using urine for diagnosis of visceral leishmaniasis (VL). Freshly collected urine and serum samples of 280 parasitologically confirmed VL patients and 66 endemic healthy controls (EHC), 48 nonendemic healthy controls (NEHC) and 45 different diseases were tested with rK39 strips. The sensitivity of rK39 in urine was 96.4% while the specificity was low varying from 66.7% in EHC, 77.08% in NEHC to 62.2% in different diseases. With serum, sensitivity was 100% whereas the specificity was 100%, 92.4% and 95.55% for the respective control groups. In the present format, the immunochromatographic strips cannot be used for the diagnosis of VL using urine samples.     

Endometrial resection mandates reliable contraception thereafter - a case report of placenta increta following endometrial ablation.

Placenta increta complicated pregnancy in a woman with a history of endometrial resection. Placentation in women with prior endometrial ablation carries a high risk for placenta accreta, increta and percreta. Contraceptive measures must be implemented after endometrial ablation and pursued until proven menopause, even in women who develop amenorrhoea postoperatively.     

Neuropathology of a 4-month-old infant born to a woman with phenylketonuria

We evaluated the brain of a 4-month-old male infant whose mother had inadequately controlled maternal phenylketonuria (MPKU). At autopsy his brain was normally developed but underweight. We found ventriculomegaly, hypoplastic cerebral white matter, and delay of myelination in late myelinating tracts without white matter astrocytosis and without chronic lesions in any gray matter structure. We compared the development of the infant's white matter tracts with published data on infant myelination. Congenital heart disease complicated the case. Abnormalities in developmental white matter may account for neurological abnormalities in infants with MPKU.     

Retention of cellular properties of PBPCs following liquid storage and cryopreservation

BACKGROUND: G-CSF-mobilized PBPCs are routinely cryopreserved within 24 hours of collection. The ability to hold PBPCs for extended time would offer increased flexibility for patients and hospitals. Retention of PBPC properties following overnight shipping, extended liquid storage at 1 to 6 degrees C, and cryopreservation was evaluated. STUDY DESIGN AND METHODS: PBPCs were stored in liquid at 1 to 6 degrees C up to 3 days, with and without shipping, and then cryopreserved in HES (6%), DMSO (5%), and HSA (4%). Thawed samples were assayed after two procedures, on dilution and after dilution and washing. Nucleated cells, viability, CD34+ cell number, committed progenitor colonies, and long-term culture-initiating cells were measured. RESULTS: CD34+ cell number, committed colony-forming cells, and long-term culture-initiating cells were essentially maintained when samples were stored in liquid for 1, 2, or 3 days before cryopreservation or after thawing and dilution. Nevertheless, significant (p < 0.05, paired t test) losses in total nucleated cell numbers were observed if thawed PBPC samples were washed before assay. CONCLUSION: PBPCs can be maintained at 1 to 6 degrees C for up to 3 days and can be cryopreserved after extended storage with properties minimally altered. Dilution alone, without centrifugation and washing, of thawed PBPC samples is a satisfactory procedure for preparing samples for in vitro assays.     

Vascular endothelium dysfunction: a conservative target in metabolic disorders

Aim

Vascular endothelium plays a role in capillary transport of nutrients and drugs and regulates angiogenesis, homeostasis, as well as vascular tone and permeability as a major regulator of local vascular homeostasis. The present study has been designed to investigate the role of endothelium in metabolic disorders.

Methods

The endothelium maintains the balance between vasodilatation and vasoconstriction, procoagulant and anticoagulant, prothrombotic and antithrombotic mechanisms.

Results

Diabetes mellitus causes the activation of aldose reductase, polyol pathway and advanced glycation-end-product formation that collectively affect the phosphorylation status and expression of endothelial nitric oxide synthatase (eNOS) and causes vascular endothelium dysfunction. Elevated homocysteine levels have been associated with increase in LDL oxidation, generation of hydrogen peroxides, superoxide anions that increased oxidative degradation of nitric oxide. Hyperhomocysteinemia has been reported to increase the endogenous competitive inhibitors of eNOS viz L-N-monomethyl arginine (L-NMMA) and asymmetric dimethyl arginine (ADMA) that may contribute to vascular endothelial dysfunction. Hypercholesterolemia stimulates oxidation of LDL cholesterol, release of endothelins, and generation of ROS. The increased cholesterol and triglyceride level and decreased protective HDL level, decreases the activity and expression of eNOS and disrupts the integrity of vascular endothelium, due to oxidative stress. Hypertension also stimulates release of endothelins, vasoconstrictor prostanoids, angiotensin II, inflammatory cytokines, xanthine oxidase and, thereby, reduces bioavailability of nitric oxide.

Conclusion

Thus, the cellular and molecular mechanisms underlying diabetes mellitus, hyperhomocysteinemia, hypercholesterolemia hypertension and hyperuricemia leads to an imbalance of phosphorylation and dephosphorylation status of lipid and protein kinase that cause modulation of vascular endothelial L-arginine/nitric oxide synthetase (eNOS), to produce vascular endothelium dysfunction.

     

Characterization of multiple CD34+ cell populations in cord blood

Unlike granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood, which show a single homogeneous population of CD34(+) cells, umbilical cord blood (CB) CD34(+) cells are present as multiple populations, CD34(regular) and CD34(bright) (the latter comprising 7.0-58.2% of the total CD34(+) cells), using the ProCOUNT trade mark procedure or with anti-CD34 labeling of immunoselected cells. The CD34(regular) population contains cells with high forward scatter (CD34(regular)FSC(high)) and with low forward scatter (CD34(regular) FSC(low)). Immunomagnetically selected CD34(+) cells, sorted into CD34(regular), CD34(regular) FSC(high), CD34(regular)FSC(low), and CD34(bright) cell populations, were used in in vitro assays: only the CD34(regular)FSC(high) population transmigrated and showed growth of colony-forming unit (CFU) and long-term culture initiating cells (LTC-IC) colonies. The absolute number of CD34(+) cells in CB samples was determined by ProCOUNT trade mark and Stem Kit trade mark enumeration protocols. In liquid stored CB units, ProCOUNT trade mark and Stem Kit trade mark count differences are accounted for by the enumeration of CD34(bright) cells. Differences between ProCOUNT trade mark and Stem Kit trade mark counts using cryopreserved/thawed samples are accounted for by increased CD34(regular) FSC(low) cell numbers (2.0 +/- 1.4% in liquid stored and 27.8 +/- 14.6% in cryopreserved/thawed samples). The ProCOUNT trade mark assay includes the nonfunctional CD34(bright) and CD34(regular)FSC(low) cells as part of the CD34(+) cell count, thereby elevating the absolute number of CD34(+) cells. Using the Stem Kit trade mark assay method of gating, CD34(bright) and CD34(regular)FSC(low) cells are not counted. Our data indicate that the CD34(regular)FSC(high) cell population has functional characteristics based on the in vitro assays and a more accurate count of these cells can be achieved using the Stem Kit trade mark assay.     

DADS Analogues Ameliorated the Cognitive Impairments of Alzheimer-Like Rat Model Induced by Scopolamine

The development of agents that affect two or more relevant targets has drawn considerable attention in treatment of AD. Diallyl disulfide (DADS), an active principle of garlic, has been reported to prevent APP processing by amyloidogenic pathway. Recently, we have reported a new series of DADS derivatives and our findings revealed that compound 7k and 7l could provide good templates for developing new multifunctional agents for AD treatment. Thus, the present study was constructed to investigate the neuroprotective effect of DADS analogues (7k and 7l) against Aβ-induced neurotoxicity in SH-SY5Y human neuroblastoma cells and in ameliorating the cognition deficit induced by scopolamine in rat model. The results indicated that compound 7k and 7l significantly inhibited Aβ_1–42-induced neuronal cell death by inhibiting ROS generation. Moreover, they prevented apoptosis, in response to ROS, by restoring normal Bax/Bcl-2 ratio. Furthermore, it was observed that scopolamine-induced memory impairment was coupled by alterations in neurotransmitters, acetylcholinesterase activity and oxidative stress markers. Histological analysis revealed severe damaging effects of scopolamine on the structure of cerebral cortex and hippocampus. Administration of compounds 7k and 7l at 5 mg/kg significantly reversed scopolamine-induced behavioural, biochemical, neurochemical and histological changes in a manner comparable to standard donepezil. Together the present findings and previous studies indicate that compounds 7k and 7l have neuroprotective and cognition-enhancing effects, which makes them a promising multi-target candidate for addressing the complex nature of AD.