Polymorphous Low-Grade Neuroepithelial Tumor of the Young (PLNTY): A Newly Described Entity of Special Radiological Significance

Intracranial granulomas are a major cause of seizures in India, the most common etiologies being neurocysticercosis and tuberculosis. However, other pathologies including rare low-grade tumors may mimic these granulomas on imaging. In this article, we presented the case of a young woman patient with drug-resistant epilepsy. On imaging, there was a small calcified lesion in the brain parenchyma. In view of concordant electroclinical and imaging data on presurgical evaluation, the lesion was excised and the patient was seizure free. On histopathological evaluation, it was found to be a polymorphous low-grade neuroepithelial tumor of the young (PLNTY) - a rare, recently reported entity that can mimic an intracranial granuloma on imaging.

Hybrid liposome-erythrocyte drug delivery system for tumor therapy with enhanced targeting and blood circulation

Liposome, a widely used drug delivery system (DDS), still shows several disadvantages such as dominant clearance by liver and poor target organ deposition. To overcome the drawbacks of liposomes, we developed a novel red blood cell (RBC)-liposome combined DDS to modulate the tumor accumulation and extend the blood circulation life of the existing liposomal DDS. Here, RBCs, an ideal natural carrier DDS, were utilized to carry liposomes and avoid them undergo the fast clearance in the blood. In this study, liposomes could either absorbed onto RBCs' surface or fuse with RBCs' membrane by merely altering the interaction time at 37°C, while the interaction between liposome and RBCs would not affect RBCs' characteristics. In the in vivo antitumor therapeutic efficacy study, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes attached onto RBCs' surfaces exhibited lung targeting effect (via RBC-hitchhiking approach) and reduced clearance in the liver, while DPPC liposomes fused with RBCs had prolong blood circulation up to 48 h and no enrichment in any organ. Furthermore, 20 mol% of DPPC liposomes were replaced with pH-sensitive phospholipid 1,2-dioleoyl-Sn-glycero-3-phosphoethanolamine (DOPE) as it could respond to the low pH tumor microenvironment and then accumulate in the tumor. The DOPE attached/fusion RBCs showed partial enrichment in lung and about 5-8% tumor accumulation, which were significantly higher than (about 0.7%) the conventional liposomal DDS. Thus, RBC-liposome composite DDS is able to improve the liposomal tumor accumulation and blood circulation and shows the clinical application promises of using autologous RBCs for antitumor therapy.

Association between overcrowded households, multigenerational households, and COVID-19: a cohort study

OBJECTIVES

The role of overcrowded and multigenerational households as a risk factor for COVID-19 remains unmeasured. The objective of this study is to examine and quantify the association between overcrowded and multigenerational households and COVID-19 in New York City (NYC).

STUDY DESIGN

Cohort study.

METHODS

We conducted a Bayesian ecological time series analysis at the ZIP Code Tabulation Area (ZCTA) level in NYC to assess whether ZCTAs with higher proportions of overcrowded (defined as the proportion of the estimated number of housing units with more than one occupant per room) and multigenerational households (defined as the estimated percentage of residences occupied by a grandparent and a grandchild less than 18 years of age) were independently associated with higher suspected COVID-19 case rates (from NYC Department of Health Syndromic Surveillance data for March 1 to 30, 2020). Our main measure was an adjusted incidence rate ratio (IRR) of suspected COVID-19 cases per 10,000 population. Our final model controlled for ZCTA-level sociodemographic factors (median income, poverty status, White race, essential workers), the prevalence of clinical conditions related to COVID-19 severity (obesity, hypertension, coronary heart disease, diabetes, asthma, smoking status, and chronic obstructive pulmonary disease), and spatial clustering.

RESULTS

39,923 suspected COVID-19 cases were presented to emergency departments across 173 ZCTAs in NYC. Adjusted COVID-19 case rates increased by 67% (IRR 1.67, 95% CI = 1.12, 2.52) in ZCTAs in quartile four (versus one) for percent overcrowdedness and increased by 77% (IRR 1.77, 95% CI = 1.11, 2.79) in quartile four (versus one) for percent living in multigenerational housing. Interaction between both exposures was not significant (β_interaction = 0.99, 95% CI: 0.99-1.00).

CONCLUSIONS

Overcrowdedness and multigenerational housing are independent risk factors for suspected COVID-19. In the early phase of the surge in COVID cases, social distancing measures that increase house-bound populations may inadvertently but temporarily increase SARS-CoV-2 transmission risk and COVID-19 disease in these populations.

Bioresorbable Polymeric Scaffold in Cardiovascular Applications

Advances in material science and innovative medical technologies have allowed the development of less invasive interventional procedures for deploying implant devices, including scaffolds for cardiac tissue engineering. Biodegradable materials (e.g., resorbable polymers) are employed in devices that are only needed for a transient period. In the case of coronary stents, the device is only required for 6-8 months before positive remodelling takes place. Hence, biodegradable polymeric stents have been considered to promote this positive remodelling and eliminate the issue of permanent caging of the vessel. In tissue engineering, the role of the scaffold is to support favourable cell-scaffold interaction to stimulate formation of functional tissue. The ideal outcome is for the cells to produce their own extracellular matrix over time and eventually replace the implanted scaffold or tissue engineered construct. Synthetic biodegradable polymers are the favoured candidates as scaffolds, because their degradation rates can be manipulated over a broad time scale, and they may be functionalised easily. This review presents an overview of coronary heart disease, the limitations of current interventions and how biomaterials can be used to potentially circumvent these shortcomings in bioresorbable stents, vascular grafts and cardiac patches. The material specifications, type of polymers used, current progress and future challenges for each application will be discussed in this manuscript.

Inclusion of Cross-Linked Elastin in Gelatin/PEG Hydrogels Favourably Influences Fibroblast Phenotype

The capacity of a biomaterial to innately modulate cell behavior while meeting the mechanical property requirements of the implant is a much sought-after goal within bioengineering. Here we covalently incorporate soluble elastin into a gelatin–poly (ethylene glycol) (PEG) hydrogel for three-dimensional (3D) cell encapsulation to achieve these properties. The inclusion of elastin into a previously optimized gelatin–PEG hydrogel was then evaluated for effects on entrapped fibroblasts, with the aim to assess the hydrogel as an extracellular matrix (ECM)-mimicking 3D microenvironment for cellular guidance. Soluble elastin was incorporated both physically and covalently into novel gelatin/elastin hybrid PEG hydrogels with the aim to harness the cellular interactivity and mechanical tunability of both elastin and gelatin. This design allowed us to assess the benefits of elastin-containing hydrogels in guiding fibroblast activity for evaluation as a potential dermal replacement. It was found that a gelatin–PEG hydrogel with covalently conjugated elastin, supported neonatal fibroblast viability, promoted their proliferation from 7.3% to 13.5% and guided their behavior. The expression of collagen alpha-1(COL1A1) and elastin in gelatin/elastin hybrid gels increased 16-fold and 6-fold compared to control sample at day 9, respectively. Moreover, cells can be loaded into the hydrogel precursor solution, deposited, and the matrix cross-linked without affecting the incorporated cells adversely, thus enabling a potential injectable system for dermal wound healing.

Diagnostic utility of the Quick Inventory of Depressive Symptomatology (QIDS-C16 and QIDS-SR16) in the elderly

OBJECTIVE

To evaluate psychometric properties and comparability ability of the Montgomery-Asberg Depression Rating Scale (MADRS) vs. the Quick Inventory of Depressive Symptomatology-Clinician-rated (QIDS-C(16)) and Self-report (QIDS-SR(16)) scales to detect a current major depressive episode in the elderly.

METHOD

Community and clinic subjects (age >or=60 years) were administered the Mini-International Neuropsychiatric Interview (MINI) for DSM-IV and three depression scales randomly. Statistics included classical test and Samejima item response theories, factor analyzes, and receiver operating characteristic methods.

RESULTS

In 229 elderly patients (mean age = 73 years, 39% male, 54% current depression), all three scales were unidimensional and with nearly equal Cronbach alpha reliability (0.85-0.89). Each scale discriminated persons with major depression from the non-depressed, but the QIDS-C(16) was slightly more accurate.

CONCLUSION

All three tests are valid for detecting geriatric major depression with the QIDS-C(16) being slightly better. Self-rated QIDS-SR(16) is recommended as a screening tool as it is least expensive and least time consuming.

SCH 503034, a mechanism-based inhibitor of hepatitis C virus NS3 protease, suppresses polyprotein maturation and enhances the antiviral activity of alpha interferon in replicon cells

Cleavage of the hepatitis C virus (HCV) polyprotein by the viral NS3 protease releases functional viral proteins essential for viral replication. Recent studies by Foy and coworkers strongly suggest that NS3-mediated cleavage of host factors may abrogate cellular response to alpha interferon (IFN-alpha) (E. Foy, K. Li, R. Sumpter, Jr., Y.-M. Loo, C. L. Johnson, C. Wang, P. M. Fish, M. Yoneyama, T. Fujita, S. M. Lemon, and M. Gale, Jr., Proc. Natl. Acad. Sci. USA 102:2986-2991, 2005, and E. Foy, K. Li, C. Wang, R. Sumpter, Jr., M. Ikeda, S. M. Lemon, and M. Gale, Jr., Science 300:1145-1148, 2003). Blockage of NS3 protease activity therefore is expected to inhibit HCV replication by both direct suppression of viral protein production as well as by restoring host responsiveness to IFN. Using structure-assisted design, a ketoamide inhibitor, SCH 503034, was generated which demonstrated potent (overall inhibition constant, 14 nM) time-dependent inhibition of the NS3 protease in cell-free enzyme assays as well as robust in vitro activity in the HCV replicon system, as monitored by immunofluorescence and real-time PCR analysis. Continuous exposure of replicon-bearing cell lines to six times the 90% effective concentration of SCH 503034 for 15 days resulted in a greater than 4-log reduction in replicon RNA. The combination of SCH 503034 with IFN was more effective in suppressing replicon synthesis than either compound alone, supporting the suggestion of Foy and coworkers that combinations of IFN with protease inhibitors would lead to enhanced therapeutic efficacy.

Hepatitis C virus NS3-4A serine protease inhibitors: SAR of moiety with improved potency

We have discovered that introduction of appropriate amino acid derivatives at P'2 position improved the binding potency of P3-capped alpha-ketoamide inhibitors of HCV NS3 serine protease. X-ray crystal structure of one of the inhibitors (43) bound to the protease revealed the importance of the P'2 moiety.

A validated chiral HPLC method for the enantiomeric separation of tolterodine tartarate

An isocratic chiral HPLC method was developed for the separation of tolterodine tartarate enantiomers. The mobile phase consists of n-hexane and isopropyl alcohol in the ratio of 980:20 (v/v) with 1 ml diethylamine and 0.6 ml trifluoroacetic acid. Chiralcel OD-H (250 mm x 4.6mm) column was used at constant room temperature. Flow rate was kept at 0.5 ml/min. This method is capable of detecting the S-isomer up to 0.1 microg/ml. The method was validated in terms of linearity, precision, limit of detection (LOD) and limit of quantification (LOQ).

Randomized, placebo-controlled trial of rofecoxib in the acute treatment of migraine

OBJECTIVE

To investigate the clinical profile of rofecoxib, a long-acting (approximately 17-hour half-life) selective cyclo-oxygenase-2 inhibitor, for the acute treatment of migraine.

METHODS

A randomized, double-blind, placebo-controlled, parallel-group study was conducted. Patients age > or =18 treated a moderate or severe migraine headache with placebo (n = 182), rofecoxib 25 mg (n = 183), or rofecoxib 50 mg (n = 192). The primary efficacy measure was headache relief (mild or no pain) 2 hours after dose.

RESULTS

The proportions of patients with migraine headache relief at 2 hours after dose were 34.3% for placebo, 54.0% for rofecoxib 25 mg (p < 0.001 vs placebo), and 56.7% for rofecoxib 50 mg (p < 0.001 vs placebo). Rofecoxib 25 and 50 mg were superior to placebo in providing pain freedom at 2 hours, 24-hour sustained headache relief, and 24-hour sustained pain freedom; in reducing photophobia, phonophobia, nausea (50 mg only), and functional disability at 2 hours after dose; and in improving some quality-of-life scores over 24 hours. More patients on rofecoxib 50 mg reported adverse events (39.6%) than patients on rofecoxib 25 mg (26.8%) or placebo (23.6%) regardless of drug relatedness; however, the incidences of drug-related adverse events were similar between treatment groups. These adverse events were generally mild or moderate in severity. The most commonly reported adverse events were dry mouth, dizziness, somnolence, nausea, dyspepsia, paresthesia, and asthenia, with similar incidences between treatment groups.

CONCLUSION

Rofecoxib 25 and 50 mg were effective and generally well tolerated for the acute treatment of migraine attacks.

Core-modified hexaphyrins; characterization of two- and four-ring inverted 26 pi aromatic macrocycles

[reaction: see text] Synthesis and structural characterization of aromatic core-modified 26 pi hexaphyrin analogues are reported.

30pi aromatic meso-substituted heptaphyrin isomers: syntheses, characterization, and spectroscopic studies

The syntheses of new aromatic 30pi heptaphyrins either through a [5 + 2] or a [4 + 3] acid-catalyzed condensation and oxidative coupling reactions of easily available and air-stable precursors are reported. The methodology followed is not only simple and efficient but also allows synthesis of a range of heptaphyrins with different heteroatoms in the core. The oxidative coupling reactions of modified tripyrranes 11 and tetrapyrranes 12 were found to be dependent on the acid concentration used and as well as the substituents present on the meso position. The change of meso aryl substituents in 11 and 12 to meso mesityl substituents gave a new heptaphyrin 18. The structural characterization has been done with extensive 1H and 2D NMR studies. The heptaphyrins reported here show rich structural diversity when the connections of the heterocyclic rings are altered, and accordingly, one ring and two ring inversions have been observed. By a judicious choice of the precursors it has been possible to control the site of ring inversion either in the bithiophene unit or in the tripyrrane unit. Theoretical calculations performed on three different heptaphyrins, 4, 5, and 17, also reveal that the inverted structures are approximately 35-40 kJ lower in energy relative to the corresponding noninverted structures. Furthermore, one of the heptaphyrins 10c shows the presence of two conformers in solution in the ratio 1:2 and no interconversion between the conformers have been observed in the temperature range of 343-228 K. On protonation, the aromaticity and the ring inversions are retained and the deltadelta values vary in the range 10.07-20.59 ppm. The energies of the Soret maxima and the HOMO-LUMO gap vary linearly with the increase in pi electrons further justifying the aromatic nature of the heptaphyrins.

Porphyrins in photodynamic therapy - a search for ideal photosensitizers

The utility of light as a therapeutic agent can be traced back over thousands of years when it was used in Ancient Egypt, India and China to treat a variety of skin diseases like psoriasis, vitiligo, rickets, cancer and psychosis. The isolation of porphyrins and their inherent tumor localizing properties coupled with its ability to generate reactive singlet oxygen when activated by light of particular wavelength which in turn results in cytotoxicity led to the emergence of a new modality namely, photodynamic therapy (PDT) as a therapeutic tool. The higher degree of selectivity offered by this modality and fewer side effects when compared to chemotherapy and radiotherapy has prompted the researchers around the globe to generate new photosensitizers. Porphyrins and expanded porphyrins are one class of molecules under intense investigation due to their photosensitizing ability for PDT application. Expanded porphyrins result from the expansion of the phi electron conjugation by increasing the number of heterocyclic rings or bridging carbons of the existing porphyrin framework. These chromophores show strong absorptions in the red region (650-800 nm) compared to that of normal 18phi porphyrins. The strong absorption of light by a water soluble nontoxic photosensitizing molecule in the therapeutic window resulting in maximum penetration of light into the tissues coupled with high singlet oxygen production will conceptualize an ideal photosensitizer. This review highlights various porphyrinoid sensitizers reported till date and their photosensitizing ability both in vitro and in vivo studies. Furthermore, the urgent need for developing ideal photosensitizer for PDT will also be highlighted.

Peptidyl diazomethyl ketones inhibit the human rhinovirus 3C protease: effect on virus yield by partial block of P3 polyprotein processing

The efficacy of a series of diazomethyl ketones (DMKs) was measured in rhinovirus-infected cultures and against the HRV14 3C protease. Their specificity and potency were confirmed against purified recombinant enzyme expressed in a yeast secretion system. An internally quenched fluorescent peptide substrate was used to assess the potency against the enzyme, obtaining a 50% inhibitory concentration (IC50) of 1 microM for both Z-L-F-Q-CHN2 and Z-V-L-F-Q-CHN2, while a lower affinity was observed for Z-F-Q-CHN2. The tripeptide Z-L-F-Q-CHN2 blocked viral replication with an IC50 value of 30 microM as judged by the reduction in viral induced cytopathy of HeLa-H1 cells, as well as a marked reduction in viral plaque formation (50% effective concentration=20 microM). Western blot analysis of viral proteins from infected cells indicates that this inhibitor works specifically by blocking viral polyprotein maturation, displaying a reduction of detectable 3C protease and an accumulation of the 3CD polypeptide. These results indicate that DMK inhibitors of the 3C protease have antiviral potency. Furthermore, the pattern of viral protein processing observed suggests that reducing the concentration of mature HRV 3C protease even in the presence of increased 3CD protein is sufficient to block proper viral processing and significantly reduce virus yield.

Cyclobutane quisqualic acid analogues as selective mGluR5a metabotropic glutamic acid receptor ligands

The conformationally constrained cyclobutane analogues of quisqualic acid (Z)- and (E)-1-amino-3-[2'-(3',5'-dioxo-1',2', 4'-oxadiazolidinyl)]cyclobutane-1-carboxylic acid, compounds 2 and 3, respectively, were synthesized. Both 2 and 3 stimulated phosphoinositide (PI) hydrolysis in the hippocampus with EC50 values of 18 +/- 6 and 53 +/- 19 microM, respectively. Neither analogue stimulated PI hydrolysis in the cerebellum. The effects of 2 and 3 were also examined in BHK cells which expressed either mGluR1a or mGluR5a receptors. Compounds 2 and 3 stimulated PI hydrolysis in cells expressing mGluR5a but not in those cells expressing mGluR1a. The EC50 value for 2 was 11 +/- 4 microM, while that for 3 was 49 +/- 25 microM. Both 2 and 3 did not show any significant effect on cells expressing the mGluR2 and mGluR4a receptors. In addition, neither compound blocked [3H]glutamic acid uptake into synaptosomal membranes, and neither compound was able to produce the QUIS effect as does quisqualic acid. This pharmacological profile indicates that 2 and 3 are selective ligands for the mGluR5a metabotropic glutamic acid receptor.

Synthesis and dopamine receptor modulating activity of novel peptidomimetics of L-prolyl-L-leucyl-glycinamide featuring alpha,alpha-disubstituted amino acids

In the present study, L-prolyl-L-leucyl-glycinamide (1) peptidomimetics 3a-3d and 4a-4d were synthesized utilizing alpha, alpha-disubstituted amino acids. These analogues were designed to explore the conformational effects of constraints at the phi3 and psi3 torsion angles. Constrained conformations were verified by the use of X-ray crystallography and circular dichroism. The effects of Pro-Leu-Gly-NH2 analogues 3a-3d and 4a-4d on enhancing rotational behavior induced by apomorphine in the 6-hydroxydopamine-lesioned animal models of Parkinson's disease were studied. The ability of these peptidomimetics to increase the binding of agonist N-propylnorapomorphine (NPA) to the dopamine D2 receptor was also examined. Extended analogue Pro-Leu-Deg-NH2 was the most active compound of this series. It was 10 times more potent and almost 2 times more effective than 1 in increasing apomorphine-induced rotations (56 +/- 15% at 1.0 mg/kg ip) and in enhancing [3H]NPA specific binding (40%).

Design, synthesis, and evaluation of azapeptides as substrates and inhibitors for human rhinovirus 3C protease

A series of azapeptides was prepared and assessed as inhibitors of the human rhinovirus 3C protease. Boc-VLFaQ-OPh was a slow-turnover substrate that gave transient (ca. 1-2 h) inhibition as it underwent hydrolysis. Boc-VLFaG-OPh gave very slow but essentially irreversible inhibition.

Synthesis and evaluation of peptidyl Michael acceptors that inactivate human rhinovirus 3C protease and inhibit virus replication

Human rhinovirus, the chief cause of the common cold, contains a positive-sense strand of RNA which is translated into a large polyprotein in infected cells. Cleavage of the latter to produce the mature viral proteins required for replication is catalyzed in large part by a virally encoded cysteine proteinase (3Cpro) which is highly selective for -Q approximately GP- cleavage sites. We synthesized peptidyl derivatives of vinylogous glutamine or methionine sulfone esters (e.g., Boc-Val-Leu-Phe-vGln-OR: R = Me, 1; R = Et, 2) and evaluated them as inhibitors of HRV-14 3C protease (3Cpro). Compounds 1 and 2 and several related tetra- and pentapeptide analogues rapidly inactivated 3Cpro with submicromolar IC50 values. Electrospray mass spectrometry confirmed the expected 1:1 stoichiometry of 3Cpro inactivation by 1, 2, and several other analogues. Compound 2 also proved to be useful for active site titration of 3Cpro, which has not been possible heretofore because of the lack of a suitable reagent. In contrast to 1, 2, and congeners, peptidyl Michael acceptors lacking a P4 residue have greatly reduced or negligible activity against 3Cpro, consistent with previously established structure-activity relationships for 3Cpro substrates. Hydrolysis of the P1 vinylogous glutamine ester to a carboxylic acid also decreased inhibitory activity considerably, consistent with the decreased reactivity of acrylic acids vs acrylic esters as Michael acceptors. Incorporating a vinylogous methionine sulfone ester in place of the corresponding glutamine derivative in 1 also reduced activity substantially. Compounds 1 and 2 and several of their analogues inhibited HRV replication in cell culture by 50% at low micromolar concentrations while showing little or no evidence of cytotoxicity at 10-fold higher concentrations. Peptidyl Michael acceptors and their analogues may prove useful as therapeutic agents for pathologies involving cysteine proteinase enzymes.

Skin adhesives and skin adhesion. 1. Transdermal drug delivery systems

The use of pressure-sensitive adhesives (PSAs) for skin-contact applications is discussed. The requirements of such adhesives in various applications are examined in detail. Commercially available classes of PSAs used for skin-contact applications are the acrylics, the polyisobutylenes, and the silicones. The main application examined in this review is transdermal drug delivery. The roles played by the PSA in two types of transdermal designs are described. Correlations between in vivo and ex vivo measurements of adhesion are discussed. Also, the reported human studies of various commercially available transdermals are examined critically, with a view to assessing the relative performance capabilities of each type of transdermal design. Finally, a comprehensive listing of currently commercialized transdermals is given.

Combining pulse compression and adaptive drive signal design to inverse filter the transducer system response and improve resolution in medical ultrasound

An adaptive inverse filtering technique has been incorporated into a medical ultrasound B-scan scheme that used a linear frequency modulated pulse for imaging. Resolution improvement is demonstrated with imaging experiments on wire targets and tissue-mimicking phantoms.

Experimental point spread function of fm pulse imaging scheme

In this paper, we have examined the possibility of incorporating pulse compression techniques into a conventional medical B-scan imaging scheme. Linear frequency modulation fm, one form of pulse coding among many others, has been used in this study. With this approach, one can overcome current peak intensity limitations. A theoretical framework that includes medium propagation effects, transducer bandwidth and diffraction effects is presented, which could be used to examine the system point spread function under this imaging scheme. A prototype experimental set-up and signal processing are described and used for simple imaging tasks in attenuating and nonattenuating media. Analysis of the experimental point spread functions shows that resolution similar to conventional short pulse imaging can be achieved. However, the existence of large range side lobe levels usually associated with pulse compression processing can degrade contrast resolution in medical ultrasound. We have considered various different factors that can affect the range side lobe levels and examined their effect either experimentally or through simulations. The technique has the potential for improving signal-to-noise ratio (SNR), maximum penetration depth and resolution without exceeding peak intensity limitations. Some possible applications are discussed that merit further evaluation. Our work demonstrates the feasibility of this technique and presents a theoretical framework that can be used in future studies aimed at evaluating image quality, system performance, and possible artifacts under such an imaging scheme.

Synthesis of oxadiazolidinedione derivatives as quisqualic acid analogues and their evaluation at a quisqualate-sensitized site in the rat hippocampus

The ability of quisqualic acid (1) to sensitize neurons to depolarization by omega-phosphono alpha-amino acid analogues of excitatory amino acids is a highly specific phenomenon and is termed the QUIS effect. In an attempt to elucidate the structure-activity relationships for this sensitization, analogues 2-6 of quisqualic acid have been synthesized. Compounds 4, 5, and 6 showed no quisqualate sensitization with respect to L-2-amino-6-phosphonohexanoic acid (L-AP6), while compounds 2 and 3 were 1/10 and 1/1000, respectively, as active as quisqualic acid in sensitizing neurons toward L-AP6.

Subcutaneous insulin pulse therapy

Subcutaneous Insulin Pulse Therapy (SIPT) consists of administration of small doses of regular insulin hourly or two hourly in the subcutaneous tissue of anterior abdominal wall through a scalp vein needle. Fifteen Non-Insulin Dependent Diabetes Mellitus (NIDDM) subjects, 8 males and 7 females with mean ages 58 +/- 8.7 years and mean duration of diabetes 11.7 +/- 9.1 years and mean BMI 25.2 +/- 5.64 were admitted for elective surgery. Glycemic control was attempted preoperatively with multiple pre-meal doses of Actrapid MC with a single injection of Monotard MC at bed time. The mean fasting plasma glucose in the 15 subjects with this insulin regimen was 321.28 +/- 69.32 mgm% and the insulin requirement per day was 106.87 +/- 35.77 units. The subjects were put on SIPT for 48 to 72 hours. During SIPT the mean fasting plasma glucose dropped to 123.2 +/- 74.11 mgm% and this marked decline in fasting plasma glucose value was statistically significant (P < .05). The insulin requirement during SIPT was 96.42 +/- 31.36 units, similar to the previous regimen (NS). The subjects were switched back to conventional insulin therapy after SIPT during which period the mean fasting plasma glucose was 125.82 +/- 34.50 mgm% and this value was again significantly lower than the pre SIPT fasting plasma glucose value (P < .05). Insulin requirement during conventional insulin therapy after SIPT was reduced to 71 +/- 21.89 units/day. This dose was significantly lower than the insulin dose administered during SIPT (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Heat stroke in long distance runners

Four cases of young cadets who developed severe heat stroke while on a cross country run in Doon Valley are reported. Physical exertion alone caused the episode in a homeothermic environment. One patient continued to have left facial nerve palsy.