The effects of crowding on adults of Echinostoma caproni in experimentally infected golden hamsters.

Fifty-nine of 60 (98%), 6-month-old male golden hamsters, Mesocricetus auratus, fed 15 (group A), 50 (group B), or 200 (group C) metacercarial cysts of Echinostoma caproni (Digenea: Echinostomatidae) were infected 7-34 days postexposure. The mean number of worms recovered in groups A, B and C were 9, 10, and 50, respectively. The percentage recovery was significantly different between group A (63%) and groups B (21%) and C (23%). The intestine was divided into three equal regions (I, II, III). Worms from group A were located in segments II and III of the small intestine whereas worms from groups B and C were distributed in all three segments. The body area, ovarian and testicular areas of worms from group A were greatest, followed in decreasing order by body and gonadal areas of worms from groups B and C. Echinostoma caproni eggs were found in the faeces of all the hamsters examined from groups A, B and C by days 9, 10 and 11, respectively. Physical damage occurred at the site of attachment of the echinostome. Pathological observations indicated the presence of enlarged lymphatic nodules with lymphocytes being the primary cellular infiltrate at the site of parasite attachment.     

Infectivity, growth, and development of Echinostoma revolutum (Digenea: Echinostomatidae) in the golden hamster, Mesocricetus auratus

All 30 female golden hamsters, Mesocricetus auratus, each fed 100 +/- 25 metacercarial cysts of Echinostoma revolutum were found to be infected 2 to 105 days post-infection with 3 to 103 (avg. 38) flukes in the small intestine. Worm wet weights averaged 0.6 mg at 9 days, 3.5 mg at 14 days, and 19 mg at 42 days; average dry weights for the identical days were 0.2, 1.2 and 5.8 mg, respectively. The average body length of worms fixed in hot (80 C) alcohol-formalin-acetic acid was 0.33 mm on day 2, 5.11 mm on day 10, 9.30 mm on day 42 and 8.56 mm on day 105. Body and gonadal area increased rapidly from about day 5 to 15 and then less rapidly. Eggs of E. revolutum were seen in the feces of 10% of the hamsters by day 9, 89% by day 10 and 100% by day 11. Eggs teased from worms, embryonated in tap water, and produced miracidia which infected lab-reared Helisoma trivolvis.     

Effects of eflornithine hydrochloride (DFMO) on fetal development in rats and rabbits

Eflornithine hydrochloride (DFMO) is a highly selective, enzyme-activated, irreversible inhibitor of the enzyme L-ornithine decarboxylase (ODC). Because of its role in the biosynthetic pathway of polyamines, ODC is essential for the growth and development of newly implanted embryonic tissue. In order to assess its effect on embryonic growth and fetal development, at various stages of gestation, DFMO was administered in the drinking water to pregnant rats and rabbits at several concentrations (from 0.03% to 3.0%) and times (from days 7, 10, or 11 through days 18 or 19). Rats were killed on day 21 and rabbits on day 29 of pregnancy (day 1 = day of insemination), and the implantations and fetuses were examined. At a concentration of 1.0% (approximately 1,270 mg/kg/day) in rats and 3.0% (approximately 915 mg/kg/day) in rabbits, maternal food and water consumption and body weight gain were significantly reduced during the treatment period, and all implantations were aborted or resorbed. At lower doses (approximately 200-600 mg/kg/day) fetuses survived to term, though in reduced numbers, and a marked reduction in average fetal weight was seen. At levels of 60 mg/kg/day or lower, there were no deleterious effects to the dams or their offspring. Few malformations were detected at any dose level by gross teratologic examination; nor were any considered to have been drug induced because of their sporadic incidence. The embryotoxicity and severe growth retardation demonstrated by these studies verify that adequate polyamine levels are essential for normal embryonic and fetal development.     

Quantification of angiogenesis in estrogen receptor-positive and negative breast carcinoma

Background

The objective of this study was to evaluate angiogenesis according to CD34 antigen expression in estrogen receptor (ER)-positive and negative breast carcinomas.

Methods

This study comprised 64 cases of infiltrating ductal carcinoma in postmenopausal women divided into two groups: Group A: ER-positive, n = 35; and Group B: ER-negative, n = 29. The anti-CD34 monoclonal antibody was used as a marker for endothelial cells. Microvessel count was carried out in 10 fields per slide using a 40× objective lens (magnification 400×). Statistical analysis of the data was performed using Student's t-test (p < 0.05).

Results

The mean number of vessels stained with the anti-CD34 antibody in the estrogen receptor-positive and negative tumors was 23.51 ± 1.15 and 40.24 ± 0.42, respectively. The number of microvessels was significantly greater in the estrogen receptor-negative tumors (p < 0.001).

Conclusion

ER-negative tumors have significantly greater CD34 antigen expression compared to ER-positive tumors.

     

Synthesis and pharmacology of 1-alkyl-3-(1-naphthoyl)indoles: steric and electronic effects of 4- and 8-halogenated naphthoyl substituents

To develop SAR at both the cannabinoid CB(1) and CB(2) receptors for 3-(1-naphthoyl)indoles bearing moderately electron withdrawing substituents at C-4 of the naphthoyl moiety, 1-propyl and 1-pentyl-3-(4-fluoro, chloro, bromo and iodo-1-naphthoyl) derivatives were prepared. To study the steric and electronic effects of substituents at the 8-position of the naphthoyl group, the 3-(4-chloro, bromo and iodo-1-naphthoyl)indoles were also synthesized. The affinities of both groups of compounds for the CB(1) and CB(2) receptors were determined and several of them were evaluated in vivo in the mouse. The effects of these substituents on receptor affinities and in vivo activity are discussed and structure-activity relationships are presented. Although many of these compounds are selective for the CB(2) receptor, only three JWH-423, 1-propyl-3-(4-iodo-1-naphthoyl)indole, JWH-422, 2-methyl-1-propyl-3-(4-iodo-1-naphthoyl)indole, the 2-methyl analog of JWH-423 and JWH-417, 1-pentyl-3-(8-iodo-1-naphthoyl)indole, possess the desirable combination of low CB(1) affinity and good CB(2) affinity.     

STAT-3 activation is necessary for ischemic preconditioning in hypertrophied myocardium

The JAK-STAT pathway is activated in the early and late phases of ischemic preconditioning (IPC) in normal myocardium. The role of this pathway and the efficacy of IPC in hypertrophied hearts remain largely unknown. We hypothesized that phosphorylated STAT-3 (pSTAT-3) is necessary for effective IPC in pressure-overload hypertrophy. Male Sprague-Dawley rats 8 wk after thoracic aortic constriction (TAC) or sham operation underwent echocardiography and Langendorff perfusion. Randomized hearts were subjected to 30 min of global ischemia and 120 min of reperfusion with or without IPC in the presence or absence of the JAK-2 inhibitor AG-490 (AG). Functional recovery and STAT activation were assessed. TAC rats had a 31% increase in left ventricular mass (1,347 +/- 58 vs. 1,028 +/- 43 mg, TAC vs. sham, P < 0.001), increased anterior and posterior wall thickness but no difference in ejection fraction compared with sham-operated rats. In TAC, IPC improved end-reperfusion maximum first derivative of developed pressure (+dP/dt(max); 4,648 +/- 309 vs. 2,737 +/- 343 mmHg/s, IPC vs. non-IPC, P < 0.05) and minimum -dP/dt (-dP/dt(min); -2,239 +/- 205 vs. -1,215 +/- 149 mmHg/s, IPC vs. non-IPC, P < 0.05). IPC increased nuclear pSTAT-1 and pSTAT-3 in sham-operated rats but only pSTAT-3 in TAC. AG in TAC significantly attenuated +dP/dt(max) (4,648 +/- 309 vs. 3,241 +/- 420 mmHg/s, IPC vs. IPC + AG, P < 0.05) and -dP/dt(min) (-2,239 +/- 205 vs. -1,323 +/- 85 mmHg/s, IPC vs. IPC + AG, P < 0.05) and decreased only nuclear pSTAT-3. In myocardial hypertrophy, JAK-STAT signaling is important in IPC and exhibits a pattern of STAT activation distinct from nonhypertrophied myocardium. Limiting STAT-3 activation attenuates the efficacy of IPC in hypertrophy.     

Synthesis and pharmacology of 11-nor-1-methoxy-9-hydroxyhexahydrocannabinols and 11-nor-1-deoxy-9-hydroxyhexahydrocannabinols: new selective ligands for the cannabinoid CB2 receptor

Fourteen novel CB2 receptor selective cannabinoids were synthesized via initial Lewis acid catalyzed rearrangement of resorcinol precursors to obtain the cannabinoid moiety. These are the 1-methoxy-9-hydroxyhexahydrocannabinols and the 1-deoxy-9-hydroxyhexahydrocannabinols, with 1',1'-dimethylalkyl side chains of four to seven carbon atoms at C-3 of the cannabinoid nucleus. The cannabinols synthesized and described in this paper all exhibit greater affinity for the CB2 receptor than for the CB1 receptor. Exceptionally high CB2 affinity was observed for 1-deoxy-9beta-hydroxy-dimethylhexylhexahydrocannabinol (JWH-361, 9, n = 3) K(i) = 2.7 nM and 1-deoxy-9beta-hydroxydimethylpentylhexahydrocannabinol (JWH-300, 9, n = 2) K(i) = 5.3 nM. In general, the stereochemistry of the 9-hydroxy group is important and the beta-orientation enhances both CB2 receptor affinity and selectivity.     

1-Bromo-3-(1',1'-dimethylalkyl)-1-deoxy-Δ(8)-tetrahydrocannabinols: New selective ligands for the cannabinoid CB(2) receptor

Δ(8)-Tetrahydrocannabinol (26), 3-(1',1'-dimethylbutyl)- (12), 3-(1',1'-dimethylpentyl)- (13), 3-(1',1'-dimethylhexyl)- (14) and 3-(1',1'-dimethylheptyl)-Δ(8)-tetrahydrocannabinol (15) have been converted into the corresponding 1-bromo-1-deoxy-Δ(8)-tetrahydrocannabinols (25, 8-11). This was accomplished using a protocol developed in our laboratory in which the trifluoromethanesulfonate of a phenol undergoes palladium mediated coupling with pinacolborane. Reaction of this dioxaborolane with aqueous-methanolic copper(II) bromide provides the aryl bromide. The affinities of these bromo cannabinoids for the cannabinoid CB(1) and CB(2) receptors were determined. All of these compounds showed selectivity for the CB(2) receptor and one of them, 1-bromo-1-deoxy-3-(1',1'-dimethylhexyl)-Δ(8)-tetrahydrocannabinol (10), exhibits 52-fold selectivity for this receptor with good (28nM) affinity.     

A nucleic acid sequence-based amplification assay for real-time detection of norovirus genogroup II

AIMS: To use molecular beacon based nucleic acid sequence-based amplification (NASBA) to develop a rapid, sensitive, specific detection method for norovirus (NV) genogroupII (GII). METHODS AND RESULTS: A method to detect NV GII from environmental samples using real-time NASBA was developed. This method was routinely sensitive to 100 copies of target RNA and intermittent amplification occurred with as few as 10 copies. Quantitative estimates of viral load were possible over at least four orders of magnitude. CONCLUSIONS: The NASBA method described here is a reliable and sensitive assay for the detection of NV. This method has the potential to be linked to a handheld NASBA device that would make this real-time assay a portable and inexpensive alternative to bench-top, lab-based assays. SIGNIFICANCE AND IMPACT OF THE STUDY: The development of the real-time NASBA assay described here has resulted in a simple, rapid (<1 h), convenient testing format for NV. To our knowledge, this is the first example of a molecular beacon based NASBA assay for NV.     

3-(1′,1′-Dimethylbutyl)-1-deoxy-Δ-THC and related compounds: synthesis of selective ligands for the CB2 receptor

The synthesis and pharmacology of 15 1-deoxy-Δ⁸-THC analogues, several of which have high affinity for the CB₂ receptor, are described. The deoxy cannabinoids include 1-deoxy-11-hydroxy-Δ⁸-THC (5), 1-deoxy-Δ⁸-THC (6), 1-deoxy-3-butyl-Δ⁸-THC (7), 1-deoxy-3-hexyl-Δ⁸-THC (8) and a series of 3-(1′,1′-dimethylalkyl)-1-deoxy-Δ⁸-THC analogues (2, n=0–4, 6, 7, where n=the number of carbon atoms in the side chain−2). Three derivatives (17–19) of deoxynabilone (16) were also prepared. The affinities of each compound for the CB₁ and CB₂ receptors were determined employing previously described procedures. Five of the 3-(1′,1′-dimethylalkyl)-1-deoxy-Δ⁸-THC analogues (2, n=1–5) have high affinity (K_i=<20 nM) for the CB₂ receptor. Four of them (2, n=1–4) also have little affinity for the CB₁ receptor (K_i=>295 nM). 3-(1′,1′-Dimethylbutyl)-1-deoxy-Δ⁸-THC (2, n=2) has very high affinity for the CB₂ receptor (K_i=3.4±1.0 nM) and little affinity for the CB₁ receptor (K_i=677±132 nM).

Scheme 3. (a) (C₆H₅)₃PCH₃⁺ Br⁻, n-BuLi/THF, 65°C; (b) LiAlH₄/THF, 25°C; (c) KBH(sec-Bu)₃/THF, −78 to 25°C then H₂O₂/NaOH.