Mg Of Ampicillin Research Articles

Phytochemical and Antimicrobial Screening of Leaf and Tuber Extracts of Tephrosia calophylla Bedd

Tephrosia calophylla, (Fabaceae) a perennial woody under shrub endemic to south India. It is one of 13 rare or threatened Tephrosia species. Commonly it is known as Adavivempali. The various species of Tephrosia is ascribed to have many medicinal and therapeutic uses. The importance of this study was to preliminary screening of different phytochemical constituents for the detection of various secondary metabolites and evaluation of antibacterial, antifungal activity and Minimum Inhibitory Concentration of the different crude extracts of tuber and leaf. Tuber and leaf both yielded more number of secondary metabolites like alkaloids, phenols, flavonoids tannins, saponins and glycosides with high quantity when compared with the leaf, consisting low quantities of phyto-constituents as steroids and in tuber consisting only tannins. Antibacterial activity of T. calophylla tuber and leaf aqueous and alcohol extracts at 10 mg/well are showing more effective activity on Bacillus subtilis (MTCC-441), Escherichia coli (MTCC-443), Pseudomonas aeruginosa (MTCC-741), Klebsealla neumoniae, Proteus vulgaris strains than the control drug Ampicillin 10 mg/well with 30.25-15.00 mm zone of inhibition. The minimum inhibitory concentration (MIC) with leaf and tuber extracts was 0.312 to 2.50 mg/ml compared to that of the 10 mg of Ampicillin. Antifungal screening of aqueous leaf extract was more effective on Candida albicans with 19.25 mm inhibition zone than Aspergillus niger at 10 mg/well compared to Nystatin the control drug at 10 mg/well with 10.2 to 12.1 mm of zone of inhibition. Fungal MIC on both organisms with leaf and tuber extracts ranges from 0.612 mg to 3 mg compared to 10 mg of Nystatin.

Chitosan-based nanoparticles sustenance and potentiation of the antibacterial effect of ampicillin against drug resistance among strains of Escherichia coli

The study seeks to evaluate nanoparticles based on chitosan for enhanced delivery of ampicillin in plasmid-mediated drug resistance. Serial dilutions of a mixed population of E. coli was plated on nutrient agar and streaked on Replica-plate 25 random colonies using MacConkey agar with or without ampicillin (100 µg/ml) daily for 96 h. Nanoparticles were prepared by cross-linking chitosan with sodium tripolyphosphate with ampicillin trihydrate adsorbed. Three different batches were prepared for optimization. The nanoparticles were optimized based on encapsulation efficiency, in vitro drug release, pH stability and microbiological assay using two laboratory strains of E. coli. Increased resistance to ampicillin due to possible plasmid transfer was established in vitro after 96 h. The encapsulation efficiency of the three batches was between 21-57 %. The drug release showed a burst effect and slow extended release over 8 h and reached a peak of about 19 % release at the 6 and 7 h in Batch A, B and C. The pH of the particles was stable over a period of 6 d. The nanoparticles containing only 0.075 mg of ampicillin dropped in an agar well plate inoculated with 1 ml of E. coli J62 lac pro trp hispFlac::Tn3 (AmpR) gave an IZD of ≥ 25 mm. Chitosan nanoparticles holds good potentials in potentiating the antibacterial effect of ampicillin against possible plasmid-mediated drug resistance

First Report of Phytophthora chlamydospora Causing Crown and Root Rot on Almond in California

First Report of <i>Phytophthora chlamydospora</i> Causing Crown and Root Rot on Almond in California

First Report of Pythium dissotocum Causing Pythium Root Rot on Hydroponically Grown Lettuce in Connecticut

In August 2016, lettuce (Lactuca sativa L.) plants presented root rot, severe wilting, and high incidence of mortality in New Haven County, CT. The plants were grown in a hydroponic deep-water culture system in a commercial greenhouse. Mature plants were stunted, the lower leaves were chlorotic, the roots were necrotic, and some plants collapsed. Lettuce roots were collected from several symptomatic plants, washed three times with sterile deionized water, blotted dry, and plated on PARP-V8 selective medium (0.005 g of pimarcin, 0.25 mg of ampicillin, 0.01 g of rifampicin, 0.10 g of pentachloronitrobenzene, 200 ml of clarified V8 juice, and 800 ml of distilled water) (Moorman et al. 2002). The plates were incubated in the dark at 21°C. Mycelium resembling the morphology of Pythium species was observed in all plates after 3 days. The isolate was identified as Pythium dissotocum based on the morphology of sexual and asexual structures following van der Plaats-Niterink’s key (van der Plaats-Niterink 1981). Colonies grown on V8-juice agar had filamentous sporangia with a dendroid structure, the oogonia were 23 μm in diameter and subglobose, the antheridia developed on unbranched stalks and were sessile, and the oospores were aplerotic. DNA was extracted from mycelial mats using a DNeasy Plant Mini Kit (Qiagen, U.S.A.), and the internal transcribed spacer (ITS) region was amplified using universal primers ITS1 and ITS4 (White et al. 1990). BLAST nucleotide analyses against publicly available Pythium sequences in GenBank confirmed that the isolates obtained were P. dissotocum with 97% query coverage and 99% identity match to GenBank accession number KM061701.1. The nucleotide sequence has been assigned the GenBank accession number MG993546. To confirm Koch’s postulates, 14-day-old lettuce seedlings, cultivar Rex (n = 25), were inoculated with 1 × 10⁵ zoospores of the isolate of P. dissotocum produced on V8 broth. After 7 days, symptoms appeared as reduced growth, necrotic roots, and chlorotic leaves. Control plants were symptomless and healthy. Roots were collected from each infected lettuce plant, and four root fragments were plated on PARP-V8 selective medium. Mycelial growth resembling Pythium was observed in all plates from inoculated plants, and no growth was observed from roots of noninoculated plants (n = 25, 1 plate per plant). The putative P. dissotocum was reisolated from the plates; DNA was extracted from mycelial mats using the same methods described above and was confirmed to be Pythium using primers ITS1 and ITS4. The amplicon was the same size as for the P. dissotocum recovered from the original plants. This is the first report of P. dissotocum being detected on lettuce in Connecticut. P. dissotocum reduces crop yield and was first reported in 1986 as a root pathogen on hydroponic lettuce in Arizona (Stanghellini and Kronland 1986). There are currently no registered synthetic-chemical fungicides in the United States for the suppression of Pythium species in hydroponic lettuce (Utkhede et al. 2009). Prevention of this disease is recommended by controlling temperature and salt levels in the nutrient solution, sanitizing surfaces, and applying preventative biological fungicides registered for Pythium root rot.

Potential of carbonic anhydrase and urease bacteria for sequestration of CO2 into aerated concrete

The present study aimed to investigate the potential of bacterial strains from cement kiln dust (CKD) to sequestrate atmospheric CO2 into aerated concrete as a functional for carbonic anhydrase (CA) and urease enzymes. Five samples of CKD was collected from Cement Industries of Malaysia Berhad (CIMA). The most potent bacterial isolates were selected and adapted to grow in 5% of CO2 and in bio-aerated concrete medium. CA enzyme was detected by using a solution of 1.8 g of p-NPA (p-nitrophenyl acetate) and 25 mg of ampicillin at 7-pH. The results of thioglycolate broth medium assay indicated that the bacterial isolates were facultative anaerobic. Furthermore, the results of candle jar test reflected that the bacterial isolates have the ability to survive with 5% of CO2 concentrations. Two bacterial isolates distinctly grow in bio-aerated concrete simulation medium, while only one bacterial isolate was the most potent and has produced in a powder form using freeze dryer to be ready to apply in bio-aerated concrete.

Determination of Ampicillin in Human Plasma by Solid-phase Extraction – Liquid Chromatography – Tandem Mass Spectrometry (SPE-LC-MS/MS) and its Use in Bioequivalence Studies

A simple, fast, sensitive and selective solid-phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) method for the quantitative analysis of ampicillin (CAS 69-53-4) in human plasma was developed using amoxicillin as internal standard, and sample extraction by solid-phase extraction (SPE). Extracts were separated by reversed-phase C18 with aqueous mobile phase (acetonitrile, 80:20, v/v) with 0.1% formic acid. The method was validated and successfully applied in a bioequivalence study of capsules 500 mg of ampicillin. Using a short running time of 2.5 min, the lower limit of quantification (LLOQ) for obtained ampicillin was 0.1 microg/ml for a plasma sample of 250 microl and a recovery of 94.38% +/- 4.05. Bioequivalence between the products was determined by calculating 90% confidence intervals (CI) for the ratio of Cmax, AUC0-t and AUC0-inf values for the test and reference products, which were within the 0.80-1.25 interval proposed by FDA and EMEA. It is concluded that the two formulations are bioequivalent in their rate and extent of absorption, and thus, may be used interchangeably.

Thermodynamic Consequences of Mutations in Vernier Zone Residues of a Humanized Anti-human Epidermal Growth Factor Receptor Murine Antibody, 528

To investigate the role of Vernier zone residues, which are comprised in the framework regions and underlie the complementarity-determining regions (CDRs) of antibodies, in the specific, high affinity interactions of antibodies with their targets, we focused on the variable domain fragment of murine anti-human epidermal growth factor receptor antibody 528 (m528Fv). Grafting of the CDRs of m528Fv onto a selected framework region of human antibodies, referred to as humanization, reduced the antibody's affinity for its target by a factor of 1/40. The reduction in affinity was due to a substantial reduction in the negative enthalpy change associated with binding. Crystal structures of the ligand-free antibody fragments showed no noteworthy conformational changes due to humanization, and the loop structures of the CDRs of the humanized antibodies were identical to those of the parent antibodies. Several mutants of the CDR-grafted (humanized) variable domain fragment (h528Fv), in which some of the Vernier zone residues in the heavy chain were replaced with the parental murine residues, were constructed and prepared using a bacterial expression system. Thermodynamic analyses of the interactions between the mutants and the soluble extracellular domain of epidermal growth factor receptor showed that several single mutations and a double mutation increased the negative enthalpy and heat capacity changes. Combination of these mutations, however, led to somewhat reduced negative enthalpy and heat capacity changes. The affinity of each mutant for the target was within the range for the wild-type h528Fv, and this similarity was due to enthalpy-entropy compensation. These results suggest that Vernier zone residues make enthalpic contributions to antigen binding and that the regulation of conformational entropy changes upon humanization of murine antibodies must be carefully considered and optimized.

First Report of Root Rot and Stem Canker Caused by Phytophthora cambivora on Noble Fir (Abies procera) for Bough Production in Norway.

In 2004, damages resembling those caused by Phytophthora spp. were observed in a 15-year-old bough plantation of noble fir (Abies procera). When removing bark upward from the roots and base of a diseased tree, a reddish brown discoloration with distinct borders to surrounding wood appeared. The discoloration extended approximately 1.5 m above ground, but only on one side of the stem. This resulted in dead basal branches (flagging) on the cankered side of the tree. Other dying trees in the same field did not show flagging symptoms but turned chlorotic to brown after being girdled by the expanding stem canker. Approximately 25% of the trees were dead or dying. Isolations were carried out from the area between healthy and diseased tissue both from roots and base of the stem of the tree with flagging symptoms. Samples were rinsed in running tap water and plated on the Phytophthora selective medium PARP (17 g of cornmeal agar, 10 mg of pimaricin, 250 mg of ampicillin, 10 mg of rifampicin, and 100 mg of pentachloronitrobenzene (PCNB) in 1 liter of water), with and without hymexazol added (50 mg/l). Morphological characters of the isolated Phytophthora sp. included nonpapillate sporangia (37 to 64 μm), internal proliferation, and characteristic hyphal swellings. The isolate was heterothallic and produced amphigynous antheridia when crossed with tester strains of P. cryptogea. The mating type was A2. The internal transcribed spacer (ITS) rDNA sequences were identical to P. cambivora (GenBank Accession No. AY880985). Thus, both morphological characters and DNA analysis supported the species identification. A pathogenesis test to fulfill Koch's postulate was carried out during 2005. Inoculation was done by placing agar with culture in the growth medium close to the roots of noble fir seedlings. Eleven weeks after inoculation, clearly visible stem canker symptoms were observed. The ITS sequences of the reisolated Phytophthora sp. were determined and found identical to P. cambivora. P. cambivora was reported to cause root rot and stem canker in a noble fir Christmas tree plantation in the United States (1). P. citricola and P. citrophthora are known to cause problems on Lawson Falsecypress/Port-Orford-cedar (Chamaecyparis lawsoniana) in Norway, but damages by Phytophthora spp. have never been reported in Abies spp. plantations or forest stands in Norway. Currently, we are also working on Phytophthora problems discovered in two different Christmas tree plantations (A. lasiocarpa and A. nordmanniana). Reference: (1) G. A. Chastagner et al. Plant Dis. 79:290, 1995.

Strategies to Improve the Therapy of Retained Fetal Membranes in Dairy Cows

In this field trial, a protocol for the treatment of retained fetal membranes (RFM) without any intrauterine therapy was compared with 3 protocols based on the intrauterine use of antibiotic pills (AP), the manual removal (MR) of the fetal membranes, or the combination of both (PR). The study was conducted on 5 commercial dairy farms in Germany. Cows with RFM for at least 24h after calving were assigned to 1 of 4 treatment groups. Cows of all groups with a rectal temperature≥39.5°C received a systemic antibiotic treatment with ceftiofur (1mg/kg per d) for 3 to 5 consecutive days. In case of continued fever after 5 treatments, cows received a different antibiotic as an escape therapy. In the reference group (REF; n=131), cows did not receive any additional treatment. All cows in group AP (n=119) received intrauterine treatment with antibiotic pills consisting of 1,000mg of ampicillin and 1,000mg of cloxacillin for 3 consecutive days. In group MR (n=121), an attempt was made to remove the fetal membranes manually, but uterine pills were not administered. In group PR (n=130), an attempt was made to remove the fetal membranes manually and all cows received a local antibiotic treatment as in group AP. All cows received 2 doses of 25mg of PGF2α: one dose between 18 and 24 d and another between 32 and 38 d postpartum. Statistical analyses were performed using binary logistic regression models and survival analyses with group REF as reference. Of all animals, 79.8% had a body temperature of≥39.5°C at least once within 10 d postpartum and were treated with ceftiofur. Occurrence of fever within 10 d postpartum was significantly lower in groups AP and PR compared with reference group REF, but was not different between groups MR and REF. Risk of receiving an escape therapy in case of fever after 5 treatments with ceftiofur did not differ among groups. Reproductive performance measures did not differ significantly between group REF and any of the comparison groups. Compared with a treatment protocol based only on systemic treatment with antibiotics for cows with a fever, neither intrauterine antibiotics nor manual removal of fetal membranes alone or in combination reduced proportions of cows needing an escape therapy nor did those treatments improve reproductive measures in the current lactation. Systemic treatment alone based on elevated rectal temperature was effective and reduced use of antibiotics compared with therapies that included intrauterine antibiotics.

First Report of Macrophomina phaseolina Causing a Crown Rot of Strawberry in Florida.

Strawberry (Fragaria × ananassa Duchesne) is produced as an annual winter crop in raised, plastic-mulched beds on 2,800 ha in west central Florida. In December 2001, a grower submitted collapsed and dying strawberry plants from a commercial field to the University of Florida in Dover. The cut crowns of affected plants revealed dark brown necrotic areas on the margins and along the woody vascular ring. Macrophomina phaseolina was isolated from pieces of infected tissue cut aseptically from the crowns and placed on a medium containing 12 g of Difco potato dextrose broth, 17 g of Bacto agar, 250 mg of ampicillin, and 100 mg of streptomycin sulfate per liter of water. The fungus produced numerous, dark, oblong sclerotia in the isolation medium after 4 to 5 days incubation at 24°C under constant fluorescent lighting. In 10-day-old cultures, sclerotia ranged in size from 55 to 190 μm long by 50 to 135 μm wide (average 105 × 74 μm). Ostiolate pycnidia bearing relatively large, broadly ellipsoidal, hyaline conidia occasionally developed on the host tissue after 8 to 10 days of incubation (2). During the 2003-2004 season, M. phaseolina was isolated from dying strawberry plants taken from the original field and two additional farms. Affected plants were often found along field margins or other areas inadequately fumigated with methyl bromide. Two single-spore isolates from different fields were tested for pathogenicity on nursery runner plants (cv. Strawberry Festival) grown for 4 weeks in the greenhouse on artificial potting soil. The fungal isolates were grown on corn meal agar at 24°C for 4 days and allowed to colonize sterile wooden toothpicks placed on the medium for an additional 5 days. Prior to use, the toothpicks were sterilized by autoclaving twice in deionized water and a third time in V8 juice. Six plants were inoculated with each isolate by inserting a colonized toothpick into each crown. Sterile, V8-infused toothpicks were inserted into the crowns of corresponding control plants. The plants were incubated in a greenhouse in a randomized complete block design with two replicates of three plants each. After 3 days, 33 to 100% of the inoculated plants developed wilting in one or more leaves. All inoculated plants collapsed or died within 2 weeks of inoculation, while the control plants remained healthy during the observation period. The pathogen was readily reisolated from inoculated plants. Charcoal rot disease caused by M. phaseolina has been reported on strawberry in France, India, and Illinois (2,3). To our knowledge, this is the first report from Florida. M. phaseolina may be an emerging threat as the Florida strawberry industry transitions from methyl bromide to other fumigants in 2005.

Mechanistic Roles of Ser-114, Tyr-155, and Lys-159 in 3α-Hydroxysteroid Dehydrogenase/Carbonyl Reductase from Comamonas testosteroni

3alpha-hydroxysteroid dehydrogenase/carbonyl reductase (3alpha-HSD/CR) from Comamonas testosteroni, a short chain dehydrogenase/reductase, catalyzes the oxidation of androsterone with NAD+ to form androstanedione and NADH. A catalytic triad of Ser-114, Tyr-155, and Lys-159 in 3alpha-HSD/CR has been proposed based on structural analysis and sequence alignment of the short chain dehydrogenase/reductase family. The 3alpha-HSD/CR-catalyzed reaction has not been kinetically analyzed in detail, however. In this study, we combined steady-state kinetics, site-directed mutagenesis, and pH profile to explore the function of Ser-114, Tyr-155, and Lys-159 in 3alpha-HSD/CR-catalyzed reaction. The catalytic efficiency of wild-type and mutants S114A, Y155F, K159A, and Y155F/K159A is 4.3 x 10(7), 7.3 x 10(4), 1.7 x 10(4), 2.4 x 10(5), and 71 m(-1)s(-1), respectively. The values of pKa on kcat/Km for the wild-type, S114A, Y155F, K159A, and Y155F/K159A are 7.2, 7.4, 8.4, 9.1, and 10.2, respectively. Mutant S114A/Y155F exhibits a pH-independent profile with 10(-5) times of wild-type activity at pH 10.5. The activity decreases as the pH lowers, which indicates that a functional group with an apparent pKa of 7.2 is involved in the general base catalysis for wild-type 3alpha-HSD/CR. The pKa shift to 9.1 for mutant K159A suggests the role of Lys-159 is to lower the pKa of the residues involved in the general base catalysis. Because pH dependence is observed for both S114A and Y155F mutants and pH independence is observed in S114A/Y155F, Tyr-155 may be important as a general base catalysis in the wild-type, whereas Ser-114 may act as a general base on mutant Y155F to catalyze the reaction.

First Report of Phytophthora nicotianae and P. citricola Associated with English Walnut Decline in Europe.

English (Persian) walnut (Juglans regia), among the most widely cultivated species of Juglans worldwide, is cultivated primarily for fruit production but also for timber. In the last 10 years, walnut decline causing leaf yellowing, sparse foliage, overall decline, and plant death has increased in Italian commercial orchards. In Italy, Phytophthora cactorum, P. cambivora, P. cinnamomi, and P. cryptogea are associated with this disease (1,4). Over the last 5 years, P. cinnamomi was the most widely isolated and destructive species (1). Recently, a different species of Phytophthora was isolated from diseased roots and soil from around lateral roots of 10 declining trees in two orchards in the Veneto Region of northern Italy. Another species of Phytophthora was isolated consistently from rotted roots of declining walnut trees in two orchards in the Campania Region of southern Italy. Phytophthora spp. were isolated directly from plant material or Rhododendron spp. leaf baiting on soil samples with PARBhy selective medium (10 mg of pimaricin, 250 mg of ampicillin [sodium salt], 10 mg of rifampicin, 50 mg of hymexazol, 15 mg of benomyl, 15 g of malt extract, 20 g of agar in 1,000 ml of H2O). Two species of Phytophthora were identified based on morphological and cultural characteristics (2). The species from trees in the Veneto Region was identified as P. nicotianae. All isolates produced papillate, spherical to obturbinate, occasionally caducous sporangia with short pedicels, terminal and intercalary chlamydospores, and were mating type A2. The species isolated from trees in the Campania Region was identified as P.citricola. Isolates were homothallic, produced semipapillate, persistent, obclavate to obpyriform sporangia, occasionally with two apices, and antheridia paragynous. Identifications were confirmed by comparing restriction fragment length polymorphism patterns of the internal transcribed spacer region of rDNA with those obtained from previously identified species of Phytophthora. Pathogenicity of two isolates each of P. citricola and P. nicotianae was tested on 2-year-old potted walnut seedlings. Inocula were prepared by inoculating sterilized millet seeds moistened with V8 broth with plugs of mycelium and incubated for 4 weeks at 20°C in the dark. Infested seeds were added to potting soil at a rate of 3% (wt/vol). One day later, pots were flooded for 48 h to promote sporulation. Ten noninoculated seedlings were used as the control. Symptoms were assessed 2 months after inoculation. Seedlings inoculated with P. nicotianae developed necrosis of feeder and lateral roots, but only limited infection of taproots. Seedlings inoculated with P. citricola developed necroses at the insertion points of lateral roots. All four isolates produced visible damage to lateral roots on inoculated plants. P. nicotianae and P. citricola were reisolated from respectively infected roots. Results from these inoculations confirmed P. nicotianae and P. citricola as root pathogens of English walnut. Both species were associated with walnut decline as reported in the United States (3). To our knowledge, this is the first report of P. nicotianae and P. citricola on J. regia in Europe.

First Report of Wilt and Dieback on Pokeweed (Phytolacca decandra) Caused by Phytophthora nicotianae.

Pokeweed (Phytolacca decandra, synonym Phytolacca americana) is a root perennial plant that produces a succulent annual stem. In late June 2001, a severe dieback occurred on a group of pokeweed plants being grown as ornamentals in a garden in Rome. Disease symptoms consisted of leaf wilting followed by collapse of the plant. Stem collars and roots had dark brown-to-black water-soaked lesions. A wet rot was observed on plants with advanced disease symptoms. Isolations, from sections of roots and stems previously washed in running tap water, were made on PARBhy selective medium (10 mg of pimaricin, 250 mg of ampicillin [sodium salt], 10 mg of rifampicin, 50 mg of hymexazol, 15 mg of benomyl, 15 g of malt extract, and 20 g of agar in 1,000 ml of H2O) (2), followed by incubation at 20°C. A species of Phytophthora identified based on morphological and cultural characteristics (1) was isolated consistently from rotted roots and collars of diseased plants. All isolates produced papillate, spherical, ovoid to obturbinate, noncaducous sporangia and terminal and intercalary chlamydospores. Hyphal swellings with hyphal outgrowths were present. Observed characteristics were similar to those described for P. nicotianae. Isolates were mating type A2 with amphigynous antheridia in paired cultures with the A1 tester isolate of P. nicotianae. Identification was confirmed by comparing restriction fragment length polymorphism patterns of the internal transcribed spacer region of ribosomal DNA with those obtained from previously identified Phytophthora species. Pathogenicity tests were conducted on 10 2-month-old potted pokeweed plants. Inoculum was prepared by inoculating sterilized millet seeds moistened with V8 broth with plugs of mycelium and growing for 4 weeks. The inoculum was added to potting soil at 3% (wt/vol), and sporulation was induced by flooding the soil for 48 h. Five uninoculated plants were used as controls. Plants were maintained outdoors and assessed for symptoms within 2 months after inoculation. Wilting, root rot, and dark brown lesions on the collar developed on inoculated plants. The pathogen was reisolated from the inoculated plants and morphologically identical to the original isolates, which confirmed P. nicotianae as the causal agent of the disease. Few diseases have been reported on Phytolacca decandra. This species is not only an invasive weed, but is also cultivated as an ornamental and medicinal plant. In addition, antiviral (PAP) and antifungal (Pa-AFP) proteins that are used as a remedy for several human and plant infections have been extracted from the plant. To our knowledge, this is the first report of P. nicotianae on pokeweed.

Comparison of two protocols for the treatment of retained fetal membranes in dairy cattle

Two protocols for the treatment of retained fetal membranes in dairy cattle were evaluated in a field trial. Cows that retained the fetal membranes for more than 12 h were assigned to two treatment groups in an alternating order. In both groups rectal temperature was measured daily for 10 days after enrollment. In Group 1 ( n=35) cows with a rectal temperature ≥39.5 °C received a systemic antibiotic treatment with 600 mg ceftiofur intramuscularly on three consecutive days. No manual removal of the fetal membranes or intrauterine treatment was conducted. In case of elevated temperature of ≥39.5 °C on Day 3 treatment was conducted for another 2 days. In Group 2 ( n=35) cows received a local antibiotic treatment (2500 mg ampicillin, 2500 mg cloxacillin) and an attempt was made to remove the fetal membranes manually. In case of a rectal temperature ≥39.5 °C 6000 mg of ampicillin were administered intramuscularly. Treatment was repeated on three consecutive days. If temperature did not decrease below 39.5 °C systemic treatment was extended for another 2 days. During 10 days of observation 33 and 34 cows showed fever, i.e. a body temperature ≥39.5 °C in Groups 1 and 2, respectively (94.3 versus 97.1%). The proportion of cows considered as cured (temperature <39.5 °C on Day 10 after enrollment) was 65.7 and 68.6% in Groups 1 and 2, respectively. All cows showed signs of chronic inflammation of the genital tract on Day 14 after calving. Within 4 weeks postpartum three (8.6%) and four (11.4%) cows were culled in Groups 1 and 2, respectively. Days to first service and days open did not differ significantly between the groups. Proportion of cows pregnant on Day 200 postpartum was 71.4 and 54.3% for Groups 1 and 2, respectively ( P>0.05). Results indicate that treatment of retained fetal membranes without intrauterine manipulation and treatment can be as effective as conventional treatment including detachment and local antibiotic treatment.

Evaluation of a Systemic Antibiotic Treatment of Toxic Puerperal Metritis in Dairy Cows

The objective of this study was to evaluate the efficacy and economic efficiency of a systemic treatment of toxic puerperal metritis in dairy cows with ceftiofur. Cows with abnormal vaginal discharge at a postpartum examination (d 4 to 6 after calving) and a rectal temperature ≥39.5°C were assigned to three treatment groups. Cows in group 1 (n = 70) received 600mg of ceftiofur intramuscularly (i.m.) on 3 consecutive days. Cows in group 2 (n = 79) received an intrauterine treatment with antibiotic pills consisting of 2500mg of ampicillin and 2500mg of cloxacillin and an additional 6000mg (i.m.) of ampicillin. This treatment was performed on 3 consecutive days. Cows in group 3 (n = 78) received the same intrauterine treatment as in group 2. In addition, 600 mg of ceftiofur was administered i.m. on 3 consecutive days. Body temperature was recorded daily for 6 d after first treatment.There were no significant differences among the groups regarding clinical efficacy at d 6 after first treatment. The cure rates based on rectal temperatures declining to below 39.5°C on d 6 after treatment were 82.9, 84.8, and 84.6% for groups 1, 2, and 3, respectively. Reproductive performance did not differ significantly between group 1 and groups 2 and 3 for any of the measures tested. A financial analysis with 87 different cost scenarios demonstrated that a systemic treatment of toxic puerperal metritis in cattle with ceftiofur is an effective alternative to the combination of local and systemic treatments.

Efficacy of Cefquinome for Treatment of Cows with Mastitis Experimentally Induced Using Escherichia coli

The efficacy of intramuscularly and intramammarily administered cefquinome was evaluated in experimental Escherichia coli mastitis in dairy cows. Forty-seven multiparous, Israeli Holstein cows in early lactation that produced at least 25 L/d of milk were used, and 400 to 750 cfu of E. coli were infused into two healthy quarters of each cow. Cows were randomly assigned to one of the following treatment groups: 1) 75mg of cefquinome administered intramammarily three times at 12-h intervals, 2) 75mg of cefquinome administered intramammarily three times at 12-h intervals and 1mg/kg of cefquinome administered intramuscularly two times at a 24-h interval, 3) 1mg/kg of cefquinome administered intramuscularly two times at a 24-h interval, and 4) 75mg of ampicillin and 200mg of cloxacillin administered intramammarily three times at 12-h intervals. All cows developed typical signs of acute clinical mastitis by 12 to 16h postinoculation. Parenteral cefquinome therapy, with or without intramammary cefquinome (groups 2 and 3), significantly improved clinical recovery and return to milk production.The bacteriological cure rates were considerably and significantly higher for cows in the groups treated with cefquinome than for cows in the group treated with ampicillin and cloxacillin. This study supported the efficacy of cefquinome in the treatment of clinical coliform mastitis in dairy cows.

Molecular Cloning and Expression of Rat Liver Aminopeptidase B

We isolated, by immunological screening of a Uni-ZAP XR cDNA library constructed from rat liver mRNAs, a cDNA clone with 2212 base pairs encoding aminopeptidase B (EC 3.4.11.6). The open reading frame encodes a 649-amino acid protein with a theoretical molecular mass of 72,545 Da and bears the consensus sequence of the zinc metalloexopeptidases, indicating that the enzyme belongs to this family, which includes aminopeptidase A, aminopeptidase N, and leukotriene-A4 hydrolase. Escherichia coli SOLR cells infected with the pBluescript phagemid excised from the Uni-ZAP XR vector containing the aminopeptidase B cDNA had a high L-arginyl-beta-naphthylamidase activity. The recombinant protein was purified to homogeneity from the recombinant E. coli extracts. The enzyme had Cl--dependent aminopeptidase activity specifically restricted to the Arg and Lys derivatives and contained 1 mol of zinc per mol of the enzyme.

Ampicillin concentrations in radicular cysts following a single oral administration of bacampicillin

1. 1. Ampicillin concentrations in cyst wall (wall) and cyst fluid (fluid) of radicular cyst and serum following a single oral administration of bacampicillin (equivalent to 500 mg of ampicillin) were measured by a paper disk method. 2. 2. The mean peak concentrations of ampicillin in wall, fluid, and serum occurred at identical times, 1.5 hr, and were 2.39 μg/g, 0.77, and 10.24 μg/ml, respectively. 3. 3. Mean ampicillin concentration ratios of wall/serum, fluid/serum, and fluid/wall at the peak time were 0.23, 0.07, and 0.40, respectively. 4. 4. Mean ampicillin concentrations in wall and fluid at the peak time exceeded MIC (minimum inhibitory concentration) for 90% (0.5 μg/ml) for clinically isolated strains of α-hemolytic Streptococci.

Intracellular targeting of antibiotics by means of biodegradable nanoparticles

Conditions for attachment of ampicillin to nanoparticles were studied. Drug-release in fetal calf serum was gradual and of zero order, due probably to the progressive bioerosion of the polymer by the esterases of the serum. Entrapment of ampicillin into nanoparticles was found to improve dramatically the therapeutic efficiency of drug in experimental intracellular infections of the mouse. On Salmonella typhimurium infected mice, 0.8 mg of ampicillin bound to nanoparticles had a greater therapeutic effect than 48 mg of free ampicillin. With experimental Listeria monocytogenes infection, the therapeutic index of ampicillin for liver bacterial counts rose at least 20-fold after its linkage to nanoparticles. These results were correlated with the tissue distribution profile of ampicillin, which concentrated mainly in the liver and the spleen, the primary foci of infection in the experimental models used. The present findings warrant further development of intracellular targeting of kantibiotics with non-liposomal polymeric carriers.

Ampicillin concentrations in human radicular granuloma following a single oral dose of bacampicillin

Ampicillin concentrations in human serum and radicular granulomas of 42 patients were determined after a single oral dose of bacampicillin (equivalent to 500 mg of ampicillin). Although wide variations were found among both serum and radicular granuloma ampicillin concentrations, measurable concentrations were found in all cases. The mean peak ampicillin concentrations in serum and radicular granulomas occurred at identical times, 1.5 hours, and were 11.19 μg/mL (range, 1.30 to 21.00 μg/mL) and 5.12 μg/g (range, 0.50 to 10.50 μg/g), respectively. The mean radicular granuloma/serum ampicillin concentration ratio at the peak time was 0.42. Ampicillin concentrations in radicular granulomas exceeded most of the minimum inhibitory concentrations for bacteria commonly isolated from odontogenic infections.