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SUMMARYFourteen strains of S. Typhi (n=13) and S. Paratyphi A (n=1) resistant to ciprofloxacin were compared with 30 ciprofloxacin decreased-susceptibility strains on the basis of qnr plasmid analysis, and nucleotide substitutions at gyrA, gyrB, parC and parE. In ciprofloxacin-resistant strains, five S. Typhi and a single S. Paratyphi A showed triple mutations in gyrA (Ser83→Phe, Asp87→Asn, Glu133→Gly) and a novel mutation outside the quinolone resistance determining region (QRDR) (Met52→Leu). Novel mutations were also discovered in an isolate (minimum inhibitory concentration 8 μg/ml) in gyrA gene Asp76→Asn and outside the QRDR Leu44→Ile. Out of 30 isolates with reduced susceptibility, single mutation was found in 12 strains only. Genes encoding qnr plasmid (qnr A, qnr B, AAC1-F) were not detected in ciprofloxacin-resistant or decreased-susceptibility strains. Antimicrobial surveillance coupled with molecular analysis of fluoroquinolone resistance is warranted for reconfirming novel and established molecular patterns of resistance, which is quintessential for reappraisal of enteric fever therapeutics.

The effect of HIV infection on immune response to diphtheria and tetanus primary immunisation was investigated in 24 HIV-1-positive multi-transfused (MT) children with thalassaemia and compared with 48 HIV-1-negative MT thalassaemic children and 36 HIV-1-negative non-transfused (NT) children in the community. Diphtheria and tetanus antibody levels in the HIV-1-positive MT group were comparable with the two HIV-negative groups. The proportions of children with antibody titres below the protective level (i.e.0.01 IU/ml) for antidiphtheria antibodies were 20.8, 16.6 and 16.6%, and 12.5, 12.5 and 13.9% for anti-tetanus antibodies in the three groups, respectively. On the other hand, delayed-type hypersensitivity (DTH) response to diphtheria and tetanus antigens was significantly depressed in the HIV-1-positive group compared with the HIV-negative controls. The mean percentages of both mature (CD20+) and immature (CD10+) B-cell counts were significantly higher in the HIV-1-positive group than in the HIV-negative MT and NT groups (p0.05). Levels of serum immunoglobulins and spontaneously secreted immunoglobulins were significantly higher in the HIV-1-positive group compared with both HIV-negative groups. The HIV-1-positive group showed a mean (SD) IL-6 of 52.9 (28.8) pg/ml compared with 23.7 (12.1) pg/ml and a detection rate of 54.2% in the HIV-negative MT group, and 23.6 (8.2) pg/ml and a 50% detection rate in the HIV-negative NT group. The IL-2 level was significantly lower (p0.05) in the HIV-1-positive group [41.7% detection rate and mean (SD) 28.8 (17.1) pg/ml] than in the HIV-negative MT and NT groups [75% and 83.3% detection rates and mean (SD) 57.2 (42.3) pg/ml and 99.3 (51.1) pg/ml, respectively]. During follow-up for 3 years, the frequency of major infections was significantly higher in the HIV-1-positive group than in the other two groups. Acute pneumonia and acute sinusitis were the predominant infections regardless of HIV status while primary bacteraemia, osteomyelitis, pyogenic meningitis and septic arthritis were common in the HIV-1-positive group. We conclude that, in HIV-1-infected children pre-immunised with DPT, DTH response to diphtheria and tetanus antigens might be more reliable than anti-diphtheria and anti-tetanus antibody levels in predicting susceptibility to major bacterial infections.

Surface properties of dried apple pomace as a function of particle size were studied in order to increase it's acceptability and utilization as source of soluble dietary fiber in processed foods. For this cleaned, dried ground pomace was sieved through 30 mesh and 50 mesh sieves to obtain 30 mesh, 50 mesh pomace and unsieved pomace was used as control. Particle size had definite effect on surface properties such as hydration capacity, fat absorption, and emulsifying properties but not much effect on whipping properties and buffering capacity (BC).

Synthesis of hydride terminated methylhydro-dimethylsiloxane copolymers from the hydrolyzates of 10, 20, 30, 50 and 70% vol.-% dichloromethylsilane with dichlorodimethylsilane have been carried out. The copolymers were characterized by IR-and 1H-NMR-spectroscopy and standard chemical analysis. They were used as curatives for a standard vinyl functional room temperature vulcanizing (RTV) silicone material based on addition cure, and the vulcanizate properties have been evaluated. The copolymers with high hydride content gave better mechanical properties and thermal stability to the vulcanizates. Methylhydro-dimethylsiloxancopolymere wurden aus den Hydrolysaten von Dichlordimethylsilan mit 10, 20, 30, 50 und 70 Vol.-% Dichlormethylsilan hergestellt. Die Copolymeren wurden IR-, 1H-NMR-spectroskopisch und chemisch charakterisiert und als Harter fur ein funktionalisiertes RTV-Siliconmaterial eingesetzt. Die Vulkanisateigenschaften wurden gepruft; die Copolymeren mit hohem Hydridgehalt verbesserten die mechanischen Eigenschaften und die thermische Stabilitat der Vulkanisate.

Extended spectrum beta-lactamases (ESBLs) are plasmid mediated enzymes capable of hydrolyzing penicillins, broad spectrum-cephalosporins and monobactams. The ESBL producing K. pneumoniae strains are being reported from around the world including India. The present study was taken up to evaluate the ESBL production and in-vitro susceptibility of K. pneumoniae isolates from a hospital. The bacterial isolates collected during 2003 included 51 K. pneumoniae biochemically confirmed isolates from 395 patients admitted in various wards of a major hospital in New Delhi. The isolates were from pus, wound, pleural fluid, urine and tracheal aspirate of patients attending respiratory, urology and burns wards. Antimicrobial susceptibility was carried out by Kirby Bauer's disc diffusion technique using NCCLS criteria. A screening of ESBL production was done by Double-disc synergy test (DDST) and using E-test ESBL strips. The frequency of resistance among K. pneumoniae for the cephalosporins (cefoxitin, cefuroxime, cefotaxime, ceftazidime, and cefepime) and non-cephalosporins (aztreonam, piperacillin, chloramphenicol and trimethoprim-sulfamethoxazole) were in the range of 39.2-88.0% and 51.0-90.2% respectively. 14 different antimicrobial resistance profiles were recognized ranging from resistance to only four (n=6, 11.7%) to as many as ten (n=9, 17.7%). Among the 51 isolates of K. pneumoniae strains, a total of 36 (70.6%) could be identified as ESBL producers, that correlates with the high frequency of multi-drug resistant K. pneumoniae The study shows alarming rise in ESBL production among K. pneumoniae strains and high rate of resistance to a wide range of cephalosporin and non-cephalosporin group of antimicrobials.

Multi drug-resistant (MDR) typhoid in India is an escalating problem. MDR isolates of Salmonella Typhi are on rise and are becoming a challenge for timely and appropriate treatment. Occurrence of per cent sensitive (%S), per cent resistant (%R) and per cent intermediate (%I) isolates may vary geographically and treatment decided on the basis of only one of these three subpopulations may lead to selection of inappropriate drug for treatment and thus treatment failure. Determination of sensitivity index (SI) of antimicrobial agents, instead of %S or %R subpopulations, may give clearer insight regarding selection of appropriate antimicrobial for treatment of typhoid. In present work, the data of sensitivity testing were analysed and interpreted both in terms of SI as well as %S, %I and %R.A total of 205 isolates of Salmonella Typhi were collected during June 2000 and August 2002 from a network of five institutes- Lady Hardinge Medical College (LHMC, N=110), Ram Manohar Lohia Hospital (RML, N=14), Majeedia Hospital (MH, N=48), Lal's Pathology Lab (LAL, N=28) and All India Institute of Medical Sciences (AIIMS, N=5) on nutrient agar slopes. Of these, 142 isolates were subjected to phage typing and biotyping at National Salmonella Phage Typing Centre, New Delhi. Five isolates resistant to 3-7 and one isolate susceptible to all of total 12 antimicrobial tested were subjected to plasmid analysis. SI for various antimicrobials was determined as the ratio of %S and %R values derived form %RIS analysis using WHONET5.18 (8.7%) isolates were susceptible to all tested antimicrobials and 124 (60%) were MDR. Of the 142 isolates, 103 were phage type E1 and biotype I. SI of antimicrobials rather than individual %S or %R or %I population presents a better criterion for interpretation of sensitivity testing data as well as selection of the most appropriate antimicrobial for timely treatment. Presence of 140, 48 and 23 Kb size plasmids in all 5 MDR isolates and none in susceptible isolate was observed.Re-emergence of chloramphenicol sensitivity in Salmonella typhi was observed in the present study. Interpretation in terms of SI criteria warrants that reintroduction of chloramphenicol at present for treatment of typhoid may rebound resistance. Current empiric therapy used for treatment of typhoid may soon become ineffective. SI being a ratio will not only eliminate geographical variation of %RIS data but also its interpretation. SI can provide guidelines for clinicians in remote areas where facilities for sensitivity testing are not available.

Maternal blood-cord samples from 171 women of middle socio-economic status who had been administered at least two doses of tetanus toxoid (TT), were assayed for tetanus antitoxins by passive haemagglutination (PHA) test. All the mother as well as cord samples had antitoxin titres > or = 0.015IU/ml, the generally accepted minimal protective level; 98 per cent of the mothers and 97 per cent of the newborns had levels > or = 0.125IU/ml. Transplacental dilution was observed in 45 per cent of the samples; the cord/maternal antitoxin ratio (C/M) of geometric mean titre (GMT) was found to be 0.72. The C/M ratio was not affected by the maternal age, parity, birth weight, and number of TT doses administered to mother. The study showed that tetanus antitoxins were diluted on the fetal side of circulation, but the protective levels of antitoxins were achieved in all the newborns as the mothers had received at least two doses of TT before delivery.

The visible range spectra of polyvinylchloride (PVC) degraded in vacuum in methylsalicylate, amylsalicylate and 2-methoxy-4-allylphenol (eugenol) are reported. On the basis of the percentages of double bonds formed in PVC the following reactivity order was assigned to the solvents methylsalicylate > amylsalicylate > eugenol. A free radical mechanism is proposed for the solvent participation. The activation energy for the overall double bond formation in methylsalicylate in the temperature range 176–208°C was found to be 21±0.5 kcal/mole. Die Spektren im sichtbaren Bereich von Polyvinylchloride(PVC), das im Vakuum in Methylsalicylat, Amylsalicylat und 2-Methoxy-4-allyphenol (eugenol) abgebaut wurde, werden beschrieben. Auf der Basis des Gehaltes der in PVC gebildeten Doppelbindungen ergibt sich hinsichtlich der Abbaugeschwindigkeit folgende Reihenfolge der Losungsmittel: Methylsalicylat > Amylsalicylat > Eugenol. Fur die Beteiligung der Losungsmittel wird ein radikalischer Mechanismus vorgeschlagen. Die Aktivierungsenergie fur die Bildung der Doppelbindungen in Methylsalicylat im Temperaturbereich von 176 bis 208 °C wurde zu 21±0,5 kcal/Mol bestiment.

The liquid phase dehydrochlorination of 1-chlorododecane (1-DDCl), 2-chlorododecane (2-DDCl), 1,1,3-trichlorononane (TCN), and dichlorononene (DCN) was investigated in the temperature range of 202—262°C in a nitrogen atmosphere. On the basis of the decomposition rate constant and activation energy the stability order for the dehydrochlorination in liquid phase was found to be 1-DDCl>2-DDCl>TCN>DCN. The influence of the solvents methyl salicylate and eugenol on the dehydrochlorination of these chloro compounds was different from their influence on the dehydrochlorination of PVC. Therefore, a molecular mechanism for dehydrochlorination believed to be operating in these chloro compounds may not be operating in PVC degradation. Die Chlorwasserstoffabspaltung aus 1-Chlordodekan (1-DDCl), 2-Chlordodekan (2-DDCl), 1,1,3-Trichlornonan (TCN) und Dichlornonen (DCN) in Stickstoffatmosphare wurde in flussiger Phase im Temperaturbereich von 202—262°C untersucht. Basierend auf der Geschwindigkeitskonstante der Zersetzungsreaktion und der Aktivierungsenergie ergibt sich als Stabilitatsskala fur die Chlorwasserstoffabspaltung in flussiger Phase: 1-DDCl>2-DDCl>TCN>DCN. Die Losungsmittel Methylsalicylat und Eugenol beeinflussen die Chlorwasserstoffabspaltung aus Polyvinylchlorid. Aus diesem Grund durfte der molekulare Mechanismus, der bei der Zersetzung dieser Chlorverbindungen wirksam ist, fur den Abbau des Polyvinylchlorids nicht zutreffend sein.

The thermal degradation of polyvinyl chloride in phenolic solvents has been investigated in an atmosphere of nitrogen in the temperature range 137–206°C. The solvents used were phenol, o-cresol, methyl, ethyl, amyl, and phenyl salicylates. The reaction was fast in phenol and slow in amyl salicylate. The rate of dehydrochlorination decreased with increasing size of the alkyl side chain in salicylates. The activation energy was low in amyl salicylate (26 kcal/mole) and high in o-cresol (29 kcal/mole), and for other solvents it was in between these two values. The results have been explained as being due to the variation in the reactivity of phenolic hydrogen and to steric factors of the various substituents. Die Chlorwasserstoffabspaltung am Polyvinylchlorid wurde in phenolischen Losungsmitteln unter Stickstoffatmosphare im Bereich von 137° bis 206°C untersucht. Phenol, o-Cresol, Methyl-, Athyl-, Amyl- und Phenylsalizylat wurden als Losungsmittel verwendet. In Phenol war die Reaktion schnell und in Amylsalizylat langsam. Mit zunehmender Grose des Alkylrestes im Salizylat nahm die Geschwindigkeit der Abspaltung des Chlorwasserstoffs ab. In Amylsalizylat war die Aktivierunsenergie niedriger (26 Kcal/mol) als in o-Cresol (29 Kcal/mol) bei den anderen Losungsmitteln lagen die Werte dazwischen. Die Ergebnisse lassen sich durch die unterschiedliche Aktivitat des phenolischen Wasserstoffs und die sterische Hinderung der verschiedenen Lsoungsmittel erklaren.

The thermal stability of commercial poly(vinyl Chloride) and its four fractions having different intrinsic viscosities (1.152–0.397 dl/g) has been investigated thermogravimetrically in the presence of atmospheric oxygen, up to a temperature of 400°C, by using the nonisothermal technique. The results indicate that the thermal stability of the polymer is inversely proportional to its intrinsic viscosity. The kinetic parameters have been evaluated for the early stages of decomposition (2% to 20%). The results have been explained on the basis of different structures of the polymer chain in fractions of high and low intrinsic viscosity.

This paper deals with pulsations in pressure and flow in the reciprocating compressor and connected piping system. A model is presented that describes the excitation at the compressor and the propagation of the pulsations in the interconnected piping. It has been adapted to digital computations to predict the pulse magnitudes in reciprocating compressor piping systems and to assess measures for their control. Predicted results have been compared with field test data and with simplified limiting condition results. A discussion of its practical application is included.

During the last decade digital computers have had a tremendous impact on the computational aspects of the various disciplines of physical sciences and engineering. In the field of catalysis and chemical kinetics computers have proved to be a valuable tool in both research and engineering applications. In most chemical reacting systems the number of reactions proceeding simultaneously is large. Manual calculations for such systems become cumbersome when more than three or four reactions are involved. Usually these reactions are accompanied by thermal effects, and often diffusional and hydrodynamical flow considerations are important [1–3]. The free radical reactions invariably include many simultaneous reactions, and the computer becomes a logical tool for such applications [4]. Another area of computer applications is the optimum design of chemical reactors where the elaborate mathematical optimization procedures are superimposed on the already complex chemical reaction system [5].

The thermal degradation of polyvinylchloride in 2-allyl phenol, 2-allyl-6-methylphenol and 2-methoxy-4-allyl phenol (eugenol) has been investigated in an atmosphere of nitrogen in the temperature range 188–218°C. The reaction is very slow in eugenol. The activation energy was lower in eugenol (40 kcal/mole) than in 2-allyl phenol (47kcal/mole). The reaction is autocatalytic. The rate of dehydrochlorination in ethylbenzoate or methylsalicylate is suppressed by addition of small quantities of eugenol. The results have been explained on the bases of a free radical mechanism for the dehydrochlorination reaction. Die Chlorwasserstoffabspaltung aus Polyvinylchlorid wurde in 2-Allylphenol, 2-Allyl-6-methylphenol und 2-Methoxy-4-allylphenol (Eugenol) unter Stickstoff im Bereich von 188-218°C untersucht. In Eugenol war die Reaktion langsam. In Eugenol war die Aktivierungsenergie niedriger (40 kcal/mole) als in 2-Allylphenol (47 kcal/mole); bei 2-Allyl-6-methylphenol lagen die Werte dazwischen. Die Reaktion ist autokatalytisch. Die Chlorwasserstoffabspaltung wird in Athylbenzoat und Methylsalizylat durch kleine Zusatze von Eugenol verlangsamt. Die Ergebnisse lassen sich durch einen Radikal-Mechanismus fur die Chlorwasserstoffabspaltung erklaren.