Novel cytotoxic diterpenes from the stem of Dysoxylum kuskusense

Three novel diterpenes, dysokusones A (1), B (2), and C (3), were isolated from the stem of Dysoxylum kuskusense as cytotoxic substances. The structures were established by spectroscopic examinations. Compounds 1, 2, and 3 were cytotoxic toward HL-60(TB) cells with EC50 values of 2.25, 6.35, and 2.37 microM, respectively. Compound 1 also displayed cytotoxicity against K-562 and NCI-H522 cells with EC50 values of 5.04 and 4.80 microM, respectively.

Low prevalence of activated protein C resistance and coagulation factor V Arg506 to Gln mutation among Korean patients with deep vein thrombosis

Activated protein C (APC) is a naturally occurring anticoagulant that interacts with factor V and VIII to inhibit the clotting cascade. The prevalence of APC resistance among Korean patients with deep vein thrombosis is ill defined. The aim of the present study was to investigate the prevalence of APC resistance and factor V Leiden mutation in Korean patients with deep vein thrombosis. The presence of factor V Leiden mutation was determined in 49 patients who visited Asan Medical Center. APC ratio was performed in 33 individuals from the above 49 patients. Three patients were excluded from the analysis because their baseline aPTT was prolonged. Resistance to APC was diagnosed when the APC ratio was below 2.55. APC resistance was documented in 8 individuals, representing 27% (8/30) of the patients on whom APC resistance test was performed. The 2 patients, who showed APC resistance, were positive for lupus anticoagulant. None of the 49 patients demonstrated factor V Leiden mutation. These findings indicate that factor V Leiden mutation is rare and APC resistance is less prevalent in Korean patients with deep vein thrombosis than in Caucasians. APC resistance not caused by factor V Leiden mutation may be a risk factor for deep vein thrombosis in this population.

Nitric oxide production after acute, unilateral hydrochloric acid-induced lung injury in a canine model

OBJECTIVE

To determine if acute unilateral lung injury induces only local or systemic inflammatory effects by measuring the production of nitric oxide (NO) and its metabolites (nitrites and nitrates) in the injured and the contralateral lung and the blood initially and 4 hrs after injury.

DESIGN

Unilateral hydrochloric acid instillation in split lung intubated subject studied over time.

SETTING

Animal physiology laboratory.

SUBJECTS

Five mongrel dogs.

INTERVENTIONS

Instillation of 10 mL of 0.1 N hydrochloric acid into one lung via a plastic catheter. Bronchoalveolar lavage (BAL) was done at 4 hrs.

MEASUREMENTS AND MAIN RESULTS

Unilateral acid instillation did not alter systemic blood pressure or cardiac output, nor did it induce arterial hypoxemia. The BAL nitrite and nitrate level on the side of injury was higher than the control side (3.6+/-1.36 vs. 1.5+/-1.58 mM, p < .05), and serum nitrites and nitrates levels also decreased from the levels before acid instillation levels (p < .05). Exhaled NO levels were measured only in three animals. The levels increased acutely on hydrochloric acid instillation from only the injured lung and returned to baseline over several minutes. However, the level of exhaled NO from the injured lung failed to increase 4 hrs after injury, despite the increase in BAL nitrites and nitrates.

CONCLUSIONS

Acute unilateral lung injury in the dog results in increased NO production that is compartmentalized to the injured lung. The increase in exhaled NO after injury is transient and does not allow one to monitor the progress of lung injury.

Synthesis and antiplatelet, antiinflammatory, and antiallergic activities of substituted 3-chloro-5,8-dimethoxy-1,4-naphthoquinone and related compounds

2-Amino (6), 2-alkylamino (7-8), 2-methoxy (9), 2-acetamido (10), and 5,8-diacetoxy (11) derivatives of the lead compound 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone (4) were synthesized, together with 6,7-dichloro-5,8dimethoxy-1,4-naphthoquinone (5), a positional isomer of 4. Antiplatelet, antiinflammatory, and antiallergic activities were evaluated, and most compounds were quite potent in all assays. Compounds 5 and 9-11 were especially active; however, 5 was ineffective against neutrophil superoxide formation, and 10 was ineffective against mast cell degranulation.

Helicobacter pylori reinfection rate and duodenal ulcer recurrence in Korea

In the short term, the eradication of Helicobacter pylori in patients with duodenal ulcer (DU) is deemed to be clearly effective; the long-term effectiveness apparently depends on the H. pylori reinfection rate. We conducted the present study to investigate the rates of H. pylori reinfection and DU recurrence in 45 patients previously cured of DU in whom H. pylori had been eradicated. These patients underwent gastroscopy and tests for H. pylori at least 1 year after eradication. In a control group comprising 31 patients with DU who were not treated with H. pylori eradication regimen, the DU recurrence rate was checked annually for 4 years. Twenty of 45 patients (44.4%) in whom the mean follow-up period was 3.5 years were again found to be H. pylori positive, and the reinfection rate was 12.8% per year. DU recurred in 8 of these 20 (40%) but not in any nonreinfected patients. In the control group, the DU recurrence rate was 61% within 1 year, 81% within 2 years, 84% within 3 years, and 90% within 4 years. The respective recurrence rates in the 45 patients in whom the bacteria had been eradicated were 0%, 4%, 13%, and 18%. The H. pylori reinfection rate was as high as 12.8% per year in Korea, but in that the DU recurrence rate is significantly lower (p < 0.01; odds ratio, 129.5) in the H. pylori-eradicated group than in the control group, the eradication of H. pylori in DU patients is effective over the long term (at least 4 years).

CDK4 down-regulation induced by paclitaxel is associated with G1 arrest in gastric cancer cells

Paclitaxel induces a cell cycle block at G2-M phase by preventing the depolymerization of microtubules and induces p53-independent apoptosis in many cancer cells. We observed that gastric cancer cells treated with paclitaxel have shown a cyclin-dependent kinase (CDK)4 down-regulation. This paclitaxel-induced CDK4 down-regulation resulted in a cell cycle arrest at G1-S phase. To confirm this observation, we prepared stable transfectants that overexpressed CDK4 and analyzed the cell cycle progression. Ectopic expression of CDK4 in SNU cells resulted in a release of paclitaxel-induced G1 arrest. The release of G1 arrest by enforced expression of CDK4 seems to make the cells more sensitive to paclitaxel-induced apoptosis. From this finding, we could then suggest that paclitaxel treatment induces both G1-S and G2-M blocks in the cell cycle progression of gastric cancer cells.

Community acquired fulminant Pseudomonas infection of the gastrointestinal tract in previously healthy infants

Three previously healthy infants presented with diarrhoea and pyrexia and deteriorated rapidly. Two patients had necrotizing bowel disease requiring aggressive surgical intervention. All survived. P. aeruginosa gastrointestinal infection in previously healthy children is an extremely rare condition with a high mortality. Ecthyma gangrenosum was present in over 60% of reported cases although often not recognized initially. A high index of clinical suspicion, including prompt recognition of ecthyma gangrenosum, is mandatory for an early diagnosis of P. aeruginosa gastrointestinal infection. Early diagnosis and treatment may improve the prognosis.

Synthesis and structure-function study about tenecin 1, an antibacterial protein from larvae of Tenebrio molitor

Tenecin 1, an inducible antibacterial protein secreted in the larvae of Tenebrio molitor, has a long N-terminal loop and common structural feature of insect defensin family corresponding to cysteine stabilized alpha/beta motif. To study the function of the N-terminal loop and disulfide bridges, N-terminal loop deleted tenecin 1, reduced tenecin 1 and tenecin 1 were chemically synthesized and their activities were measured. N-terminal loop deleted tenecin and reduced tenecin 1 did not show antibacterial activity. Circular dichroism (CD) spectroscopy data revealed that the alpha-helical content of tenecin 1 and the other proteins increased in the presence of 50% (v/v) trifluoroethanol (TFE) and the alpha-helical content of tenecin 1 was much higher than that of the other proteins in buffer with or without 50% (v/v) TFE. These results suggest that disulfide bridges are necessary for the activity structure and the N-terminal loop plays an important role in the increase of alpha-helix in the membrane mimetic environment and the activity.

Synthesis and cytotoxicity of 2-acetyl-4,8-dihydrobenzodithiophene-4, 8-dione derivatives

2-Acetyl-4,8-dihydrobenzo[1,2-b:4,5-b']dithiophene-4,8-dione (9) and 2-acetyl-4,8-dihydrobenzo[1,2-b:5,4-b']dithiophene-4,8-dione (19), together with 10 related mono- and disubstituted derivatives, were synthesized and evaluated in vitro by NCI against eight cancer types. All compounds showed significant activity against melanoma, HL-60 leukemia, NCI-H23 non-small-cell lung cancer, OVCAR-3 ovarian cancer, and MDA-MB-435 and MDA-N breast cancer cell lines. Compound 11, 2-(1'-acetoxyethyl)-4,8-dihydrobenzo[1,2-b:4,5-b']dithiophene-4, 8-dione, showed the highest overall potency (mean GI50 = 40 nM).

Anti-AIDS agents. 34. Synthesis and structure-activity relationships of betulin derivatives as anti-HIV agents

Succinyl and 3'-substituted glutaryl betulin derivatives showed stronger anti-HIV activity and higher therapeutic index (TI) values than their dihydrobetulin counterparts, with ratios of 1.2:1 to 15:1 (cf. 7 and 15, 9 and 17, 10 and 18, 11 and 19, and 12 and 20). For various 3'-substituted glutaryl compounds, the order of anti-HIV effects, from strong to weak inhibition, was 3',3'-dimethyl, 3'-methyl, 3'-ethyl-3'-methyl, followed by 3',3'-tetramethylene glutaryl derivatives (10 > 9 > 11 > 12, 18 > 17 > 19 > 20). The most potent compound, 10, has two 3',3'-dimethylglutaryl groups and displays significant anti-HIV potency with an EC50 value of 0.000 66 microM and a TI of 21 515. Results for compounds (22 and 23) without a C-3 acyl group confirmed the importance of the C-3 acyl group to the anti-HIV effect. With 3',3'-tetramethylene glutaryl derivatives, triacyl 29 showed stronger inhibition than diacyl 12; in contrast, 3',3'-dimethylglutaryl compounds displayed opposite results. 3-Keto compounds (35 and 36) and 2,3-dihydro compounds (39 and 40) had EC50 values in the range of 4.3-10.0 microM, suggesting that A ring modification led to decreased potency. The reduced activity of amide (33 and 34), ester (41), and oxime (42) analogues suggested that the orientation and linkage of the C-3 acyl side chain play crucial roles in the potent anti-HIV activity. Finally, replacing the C-28 acyl group with a bulky non-carboxylic group produced a less potent compound (44). In the study of mechanism of action, our results indicated that fusion is not the primary target for the anti-HIV activity of 10. It appears to inhibit HIV replication at a late stage of the viral life cycle, i.e., after viral protein synthesis.

Antitumor agents. Part 186: Synthesis and biological evaluation of demethylcolchiceinamide analogues as cytotoxic DNA topoisomerase II inhibitors

Demethylation of colchiceinamide (2) and its analogues (3-10) afforded a novel class of mammalian DNA topoisomerase II inhibitors (2a-10a) without displaying tubulin inhibitory activity. All target compounds inhibited the catalytic activity of topoisomerase II at drug concentrations at 100 microM. An in vitro cytotoxicity assay indicated that compounds 3a and 8a were strong and tissue-selective cytotoxic agents against the MCF-7 breast cancer cell line (IC50 = 0.36 and 0.48 microgram/mL, respectively) and the CAKI-1 renal cancer cell line (IC50 = 0.72 and 0.96 microgram/mL, respectively).

Distributional patterns of phospholipase C isozymes in rat kidney

As the first step to investigate the physiological function of phospholipase C (PLC), we determined the distribution patterns of PLC isozymes in normal rat kidneys using Western blotting analysis and immunohistochemistry. Western blotting analysis was performed in four regions (cortex, outer stripe and inner stripe of the outer medulla, and the inner medulla). PLC-beta1 and beta3 were detected in the inner stripe of the outer medulla and the inner medulla. PLC-gamma1 was distributed homogeneously along the corticomedullary axis. PLC-gamma2 was observed in the medulla and PLC-delta1 showed a gradual increase from the cortex to the inner medulla. In contrast, no PLC-beta4 was detected in all regions. On immunohistochemistry, the immunoreactivities to PLC antibodies were observed as follows: PLC-beta1, from the thick ascending limb (TAL) to the inner medullary collecting tubule (IMCT); PLC-beta3, in the glomerulus (Glm), the ascending thin limb (ATL) and the collecting tubule; PLC-beta4, Glm, the proximal convoluted tubule (PCT), ATL, the distal convoluted tubule, the connecting tubule, and the collecting tubules; PLC-gamma1, PCT, TAL and IMCT; PLC-delta1, homogeneously from PCT to IMCT. PLC-beta3 immunoreactivities were detected in the nuclei of the TAL, ATL, outer medullary collecting tubule (OMCT) and IMCT. PLC-beta4 and gamma2 were observed in Glm, MTAL, ATL, OMCT and IMCT. These results suggest the intrarenal site-specific existence of PLC isozymes that may regulate kidney functions through the PLC-mediated signal transductions.

Crystal structure of the Ebola virus membrane fusion subunit, GP2, from the envelope glycoprotein ectodomain

We have determined the structure of GP2 from the Ebola virus membrane fusion glycoprotein by X-ray crystallography. The molecule contains a central triple-stranded coiled coil followed by a disulfide-bonded loop homologous to an immunosuppressive sequence in retroviral glycoproteins, which reverses the chain direction and connects to an alpha helix packed antiparallel to the core helices. The structure suggests that fusion peptides near the N termini form disulfide-bonded loops at one end of the molecule and that the C-terminal membrane anchors are at the same end. In this conformation, GP2 could both bridge two membranes and facilitate their apposition to initiate membrane fusion. We also find a heptad irregularity like that in low-pH-induced influenza HA2 and a solvent ion trapped in a coiled coil like that in retroviral TMs.

Relevance of proteins C and S, antithrombin III, von Willebrand factor, and factor VIII for the development of hepatic veno-occlusive disease in patients undergoing allogeneic bone marrow transplantation: a prospective study

Factors that enhance hypercoagulability following BMT may have a pathogenetic role in VOD. To investigate the relevance of hemostatic parameters for the development of VOD, we prospectively measured protein C, protein S, antithrombin III (AT III), von Willebrand factor, and factor VIII in 50 consecutive patients undergoing allogeneic BMT. Each parameter was determined before conditioning, on day 0 of BMT and weekly for 3 weeks, and patients were monitored prospectively for the occurrence of VOD. VOD occurred in 26 patients at median post-BMT day 8.5 (range, day -2 to 17). Thirteen patients had mild, 10 had moderate and three had severe VOD. No coagulation parameters were significantly different at the baseline or on day 0 of BMT between patients with no/mild VOD and moderate to severe VOD. On day 7 and thereafter, levels of protein C and AT III were significantly lower in patients with moderate to severe VOD when compared to patients with no/mild VOD. Levels of protein C and AT III decreased before the clinical onset of VOD in patients with moderate to severe VOD. Early post-BMT reduction of these parameters may indicate the development of moderate to severe VOD.

Structure of the hemagglutinin precursor cleavage site, a determinant of influenza pathogenicity and the origin of the labile conformation

The membrane fusion potential of influenza HA, like many viral membrane-fusion glycoproteins, is generated by proteolytic cleavage of a biosynthetic precursor. The three-dimensional structure of ectodomain of the precursor HA0 has been determined and compared with that of cleaved HA. The cleavage site is a prominent surface loop adjacent to a novel cavity; cleavage results in structural rearrangements in which the nonpolar amino acids near the new amino terminus bury ionizable residues in the cavity that are implicated in the low-pH-induced conformational change. Amino acid insertions at the cleavage site in HAs of virulent avian viruses and those of viruses isolated from the recent severe outbreak of influenza in humans in Hong Kong would extend this surface loop, facilitating intracellular cleavage.

Sequence analysis of the nucleocapsid protein gene of the porcine reproductive and respiratory syndrome virus Taiwan MD-001 strain

The 3'-portion of the genome from a Taiwan isolate of porcine reproductive and respiratory syndrome (PRRS) virus, strain MD-001, was cloned and sequenced. The resultant 549 nucleotides contained an open reading frame with a coding capacity of 123 amino acids (predicted Mr 13,600). The predicted protein corresponds to the nucleocapsid protein, the gene product of ORF7. Comparative sequence analysis of several known PRRSV strains indicated that this protein showed the highest degree of amino acid similarity to the US VR2332 and the Canadian IAF-Exp91 strains (92.7%) and the least to the Dutch Lelystad strain (56.5%). The phylogenic trees constructed on the basis of the known PRRSV nucleotide sequences indicated that MD-001 strain belongs to the North American strain cluster and that it is distinct from the European virus.

Recent advances in the discovery and development of flavonoids and their analogues as antitumor and anti-HIV agents

Antitumor and anti-HIV flavonoids and their analogues will be reviewed with emphasis on those discovered in our laboratory. The active antitumor compounds include the antileukemic tricin (1) and kaempferol-3-O-beta-D-glucopyranoside (2) from Wikstroemia indica, the cytotoxic hinokiflavone (3) from Rhus succedanea, the cytotoxic isoflavone (8) from Amorpha fruticosa, two dihydroxypentamethoxyflavones (9, 10) from Polanisia dodencandra. The development of synthetic 2-phenyl-4-quinolones as potent cytotoxic antimitotic flavonoid analogues and 2-phenylthiochromen-4-ones as potent antitumor flavonoid analogues will be presented. Selected results from other laboratories and antitumor-related biological studies also will be discussed. Flavonoids have also been investigated as potential anti-HIV agents. In our laboratory, acacetin-7-O-beta-D-galactopyranoside (131) from Chrysanthemum morifolium and chrysin (102), as well as apigenin-7-O-beta-D-glucopyranoside (130), from Kummerowia striata, have been found to exhibit anti-HIV activity. In other studies, some flavonoids and related compounds have been investigated as inhibitors of HIV-1 reverse transcriptase, protease, and integrase. The isolation and structural modification of such plant-derived active principles provide a continuing source of potential antitumor and anti-HIV agents.

Functional dissociation between local and systemic immune response during anti-melanoma peptide vaccination

Peptide vaccination against tumor Ags can induce powerful systemic CTL responses. However, in the majority of patients, no tumor regression is noted. To study this discrepancy, we analyzed CTL reactivity in a melanoma patient (F001) vaccinated with g209-2M peptide, a single residue variant of gp100(209-217). G209/g209-2M-reactive CTL were identified in post- but not prevaccination PBL. Limiting dilution analysis identified one predominant CTL clone (C1-35), with TCR Vbeta6s2, recognizing g209/HLA-A*0201-expressing targets. Additionally, two autologous melanoma lines (F001TU-3 and -4) and 20 separate tumor-infiltrating lymphocyte cultures were generated from a fine needle aspirate of a metastatic lesion progressing after initial response to vaccination. Both F001TU did not express gp100 and were not recognized by C1-35. Loss of gp100 by F001TU correlated with a marked reduction of gp100 expression in the same metastatic lesion compared with prevaccination. Thus, ineffectiveness of C1-35 and tumor progression could be best explained by loss of target Ag expression. Interestingly, 12 of 20 tumor-infiltrating lymphocyte cultures recognized F001TU, but none demonstrated g209/g209-2M reactivity, suggesting a functional dissociation between systemic and local immune response. This study suggests that vaccination effects must be analyzed in the target tissue, rather than in the systemic circulation alone.

Dna2 of Saccharomyces cerevisiae possesses a single-stranded DNA-specific endonuclease activity that is able to act on double-stranded DNA in the presence of ATP

To gain further insights into the biological functions of Dna2, previously known as a cellular replicative helicase in Saccharomyces cerevisiae, we examined biochemical properties of the recombinant Dna2 protein purified to homogeneity. Besides the single-stranded (ss) DNA-dependent ATPase activity as reported previously, we were able to demonstrate that ssDNA-specific endonuclease activity is intrinsically associated with Dna2. Moreover, Dna2 was capable of degrading duplex DNA in an ATP-dependent fashion. ATP and dATP, the only nucleotides hydrolyzed by Dna2, served to stimulate Dna2 to utilize duplex DNA, indicating their hydrolysis is required. Dna2 was able to unwind short duplex only under the condition where the endonuclease activity was minimized. This finding implies that Dna2 unwinds only partially the 3'-end of duplex DNA and generates a stretch of ssDNA of limited length, which is subsequently cleaved by the ssDNA-specific endonuclease activity. A point mutation at the conserved ATP-binding site of Dna2 inactivated concurrently ssDNA-dependent ATPase, ATP-dependent nuclease, and helicase activities, indicating that they all reside in Dna2 itself. By virtue of its nucleolytic activities, the Dna2 protein may function in the maintenance of chromosomal integrity, such as repair or other related process, rather than in propagation of cellular replication forks.

Synthesis and anticancer evaluation of certain gamma-aryloxymethyl-alpha-methylene-gamma-phenyl-gamma-butyrolactones

Certain gamma-aryloxymethyl-alpha-methylene-gamma-phenyl- gamma-butyrolactones were synthesized and evaluated for their anticancer activity. These compounds demonstrated a strong growth inhibitory activity against leukemia cell lines but are relatively inactive against non-small cell lung cancers and CNS cancers. The anticancer potency for aryl portion is in an order of quinoline > 8-hydroxyquinoline > 2-methylquinoline >> naphthalene >> benzene.

Synthesis and cytotoxicity of acetyl-4H,9H-naphtho[2,3-b]thiophene-4,9-diones

Several new acetyl-4H,9H-naphtho[2,3-b]thiophene-4,9-diones were synthesized and evaluated for in vitro cytotoxicity by NCI against seven cancer cell types. 2,7-Diacetyl naphtho[2,3-b]thiophene-4,9-dione (9) showed significant cytotoxicity against leukemia cells with log GI50 values of -7.61 against SR cells and -7.18 against MOLT-4 cells. 3-Acetyl-naphtho[2,3-b]thiophene-4,9-dione (6) also demonstrated potent cytotoxicity in the latter cell line with log GI50 < -8.

Long-term effect of Helicobacter pylori eradication on gastric metaplasia in patients with duodenal ulcer

There have been conflicting reports on the effect of Helicobacter pylori eradication on gastric metaplasia in the duodenal bulb (DGM). In the present study, we have investigated the relationships between DGM and H. pylori by examining whether or not H. pylori-positive patients had more DGM than H. pylori-negative patients with nonulcer dyspepsia (NUD) or duodenal ulcer (DU), and by examining the effect of eradication of H. pylori on the prevalence and the extent of DGM during the long-term up to 4 years. Fifty H. pylori-positive and seven H. pylori-negative patients with DU and 23 H. pylori-positive and 23 H. pylori-negative NUD subjects were studied. Two duodenal bulb biopsy specimens were taken for histologic evaluation and the presence and the extent of DGM were evaluated. The extent of DGM was classified as none (grade 0), focal (grade 1), multifocal (grade 2), and diffuse type (grade 4). In H. pylori-positive patients with DU, follow-up gastroscopy was conducted 4 weeks, 1 year, and 4 years after H. pylori eradication. DGM was significantly (p < 0.001) more common (DU: 93%, NUD: 22%) and significantly (p < 0.001) greater in extent for patients with DU than for NUD subjects (DU: 1.89, NUD: 0.28). Neither the prevalence nor the extent of DGM was affected by H. pylori status in patients with DU or NUD; the prevalence (extent) of DGM of H. pylori-positive and -negative patients with DU were 96% (1.94) and 71% (1.57), respectively. In the 43 "H. pylori-eradicated" group, initial prevalence of DGM was 95% and those of 4 weeks, 1 year, and 4 years after eradication were 91%, 96%, and 79%, respectively. The initial extent of DGM was 1.93, and those of 4 weeks, 1 year, and 4 years after eradication were 1.90, 1.88, and 1.57, respectively. In conclusion, the prevalence and the extent of DGM were not related to H. pylori in patients with DU or NUD. In addition, the prevalence and the extent of DGM did not change until 1 year after H. pylori eradication in patients with DU, and decreased to the initial level of the H. pylori-negative DU group but without statistical significance after 4-year follow-up.

Susceptibility of penicillin-susceptible and -resistant pneumococci to CFC-222, a new fluoroquinolone

The in-vitro activity of 12 antibacterial agents against 98 clinical isolates of Streptococcus pneumoniae, including 54 penicillin-resistant strains, was determined by a standardized broth microdilution method. CFC-222, vancomycin and imipenem were the most active agents, with an MIC90 of 0.5 mg/L for the test strains. CFC-222 was 16-fold more potent than ciprofloxacin and ofloxacin against all strains tested, including both penicillin-susceptible and -resistant strains. The anti-pneumococcal activity of fluoroquinolones was not affected by penicillin susceptibility. These results indicate that CFC-222 is potentially useful for treating infection caused by penicillin-resistant strains of S. pneumoniae.