Efficacy of a potentized homoeopathic drug (Arsenicum Album-30) in reducing genotoxic effects produced by arsenic trioxide in mice: comparative studies of pre-, post- and combined pre- and post-oral administration and comparative efficacy of two microdoses

OBJECTIVE

To examine the comparative efficacies of Arsenicum Album 30C and 200C and three administrative modes in protecting against the genotoxic effects produced by Arsenic trioxide injection in mice.

DESIGN

Healthy mice, Mus musculus, were intraperitoneally injected with a 0.004% solution of As2O3 @1 ml/100 gms of body weight. Genotoxic effects were assessed through chromosome aberrations (CA), micronucleated erythrocytes (MNE), mitotic index (MI) and sperm head anomaly (SHA) studies, keeping suitable succussed alcohol fed (positive) and As2O3 untreated normal (negative) controls. The As2O3 treated mice were divided into three subgroups, which were orally administered with the drug a) prior to, b) after and c) both prior to and after injection of As2O3 at specific fixation intervals.

RESULTS

While the CA, MNE and SHA were reduced in the drug fed series as compared to respective controls, the MI showed an apparent increase. The combined pre- and post-feeding of Arsenicum album was found to be most effective in reducing the genotoxic effects of As2O3 i200C was more effective than 30C.

CONCLUSION

Arsenicum Album reduces the genotoxic effect of arsenic poisoning.

Clinical effects and maternal and fetal plasma concentrations of 0.5% epidural levobupivacaine versus bupivacaine for cesarean delivery

BACKGROUND

Bupivacaine exists as a mixture of two enantiomers, levobupivacaine and dexbupivacaine. Data suggest that levobupivacaine has equal local anesthetic potency, with reduced potential for central nervous system and cardiovascular toxicity. The present study compares the efficacy of 0.5% levobupivacaine with 0.5% bupivacaine for epidural anesthesia in parturients undergoing elective cesarean delivery.

METHODS

Sixty healthy obstetric patients undergoing elective cesarean delivery with epidural anesthesia completed the study. Patients were randomized to receive 30 ml of either 0.5% levobupivacaine or 0.5% bupivacaine in a double-blind fashion. The efficacy endpoint measures included onset, offset, and quality of anesthesia. Neonatal blood gas analyses, Apgar score determinations, and neurobehavioral examinations were performed. Venous samples for pharmacokinetic studies and serial electrocardiograms were obtained in 10 patients in each group.

RESULTS

Levels of sensory block, motor block, muscle relaxation, and overall quality of anesthesia did not differ between groups. The frequency of hypotension was 84.4% in the levobupivacaine group and 100% for the bupivacaine group (P < or = 0.053). No significant difference in observed maximum concentration of drug after dosing or area under the plasma drug concentration versus time curve were seen. The maximum concentrations were 1.017 and 1.053 microg/ml, and the areas were 4.082 and 3.765 h(microg/ml) for the levobupivacaine and bupivacaine groups, respectively. Umbilical vein-to-maternal vein ratios were 0.303 for the levobupivacaine group and 0.254 for the bupivacaine group.

CONCLUSIONS

The use of epidural 0.5% levobupivacaine for cesarean delivery results in equally efficacious anesthesia compared with 0.5% bupivacaine. Pharmacokinetic parameters were similar in the two groups.

Anesthesia for in vitro fertilization: the addition of fentanyl to 1.5% lidocaine

Ultrasonically guided transvaginal oocyte retrieval is relatively short procedure that is performed on an out-patient basis. The optimal anesthetic technique should allow good surgical anesthesia with minimal side effects, a short recovery time, and, if possible, a high rate of successful pregnancy. Spinal anesthesia is often used in this institution, as well as many others, for this procedure. The addition of fentanyl may be effective for both intraoperative and postoperative pain relief. We assessed the effect of adding fentanyl to 1.5% lidocaine in women undergoing ultrasonically guided oocyte retrieval. Seventy-eight women were randomized to receive 45 mg of hyperbaric 1.5% lidocaine with or without 10 microg of fentanyl. Visual analog scale (VAS) pain scores were lower in the operating room (OR) (P < 0.05) and postanesthesia care unit (PACU) (P < 0.0005) for the group that received fentanyl. In addition, the amount of narcotic required in the PACU was less in the fentanyl group (P < 0.005). There was no difference in VAS scores the evening of or 24 h after the procedure. The amount of analgesics and narcotics required after discharge was the same for both groups. Timed variables, such as time to urination, ambulation, and discharge, were the same for both groups of women. The addition of fentanyl to lidocaine for transvaginal oocyte retrieval results in a more comfortable patient in the OR and PACU.

IMPLICATIONS

This study demonstrates that when fentanyl is added to a local anesthetic, lidocaine, with spinal anesthesia for egg retrieval procedures, patients are more comfortable during the procedure compared with those who receive lidocaine alone. In addition, the narcotic requirements of patients are less in the postanesthesia care unit.

Activation of neuroblast proliferation in explant culture of the Drosophila larval CNS

The developmental control of neuroblast proliferation is absolutely required for the assembly and function of the central nervous system. A lethal mutation in trol results in the failure of quiescent neuroblasts to begin division at the appropriate time. I have established a culture system in which quiescent neuroblasts in explants of Drosophila larval CNSs initiate cell division in vitro to normal in vivo levels. This activation requires removal of the CNS for culture after a specific developmental stage and the presence of fetal calf serum or a larval extract in the medium. Either supplement is effective when heat-treated. Substitution of the steroid hormone ecdysone or the non-steroidal ecdysone analog RH5992 for either fetal calf serum or larval extract also results in activation of neuroblast proliferation. Culture of trolsd CNSs with wildtype larval extract or ecdysone results in the defective neuroblast proliferation phenotype observed in trol mutants in vivo, while culture of wildtype CNSs with trolsd extract produces normal neuroblast proliferation.

Evidence for organochlorine contamination in tissues of salmonids in Lake Tahoe

To evaluate the extent of organochlorine pollution in the Sierra Nevada ecosystem, residues of certain organochlorines in lake trout and Kokanee fish from Lake Tahoe, an alpine lake located between the Sierra Nevada Mountain Range and the Carson Range of California and Nevada, were analyzed. Multiresidue analysis in fish muscle revealed wet weight concentrations of total polychlorinated biphenyls (PCBs) in the range 18 to 430 ppb and of p,p'-DDE in the range 5 to 85 ppb in the two fish species studied. In one large lake trout sample (6.6 kg), which was studied in more detail as compared with others, residue levels of PCB (267 ppb), toxaphene (154 ppb), a chlordane mixture (78 ppb), and a DDT mixture (154 ppb) were found in muscle. Full spectra of specific PCB congeners and p,p'-DDE were obtained from fish fat tissues and their identities were confirmed using gas chromatography/mass spectrometry (GC-MS). The results of total PCB analysis indicated that residues found in fish consisted mostly of moderately (tri- to tetrachloro-) to highly (penta- to heptachloro-) chlorinated biphenyls. For all fish residues analyzed, the best match to PCB residue profiles was with Aroclor 1260 or 1262.

Influence of cadmium intoxication on hepatic lipid peroxidation, glutathione level, and glutathione S-transferase and gamma-glutamyl transpeptidase activities: correlation with chromosome aberrations in bone marrow cells

We examined whether there was any correlation between chromosome aberrations (CAs) in bone marrow cells with hepatic lipid peroxidation (LPO), reduced glutathione (GSH) level, glutathione S-transferase (GST), and gamma-glutamyl transpeptidase (GGT) activity after cadmium (Cd) intoxication in both a dose- and a time-dependent manner. Cadmium chloride was administered subcutaneously in doses of 0.5, 1.5, 2.5, and 5.0 mg/kg body weight to Swiss albino Balb/c male mice. The animals were exposed for 8, 16, and 24 days, i.e., 4, 8, and 12 doses, respectively. Biochemical parameters were measured in hepatic tissue for a correlation with chromosome aberrations in bone marrow. With the increment of dose and advancement of time points, the biochemical, as well as the cytogenetic, parameters altered significantly. Hepatic lipid peroxidation and GGT activity increased significantly along with an increased percentage of chromosome aberrations in the bone marrow, but the hepatic reduced glutathione level and GST activity were found to decrease following Cd administration. Up to 5.0 mg Cd/kg body weight, lipid peroxidation did not exhibit threshold levels of toxicity as shown by the two-way (fixed effect) analysis of variance test. In contrast, the observed values of reduced glutathione levels, GST and GGT activity, and chromosome aberrations in bone marrow showed threshold activity levels. Therefore, there might be a relationship between an increase in the frequency of chromosome aberrations, elevated lipid peroxidation, and depleted glutathione levels and GST and GGT activity. The clastogenic efficacy of Cd may be mediated through the biochemical pathways.

Expression of cyclin E or DP/E2F rescues the G1 arrest of trol mutant neuroblasts in the Drosophila larval central nervous system

The trol locus of Drosophila regulates the timing of neuroblast proliferation. In trol mutants, quiescent neuroblasts fail to begin division. We have investigated this cell cycle arrest to examine trol function. Induced expression of cyclin E or DP/E2F in trol mutants results in normal levels of dividing neuroblasts, while cyclin B expression has no effect. cyclin E expression is lower in the trol mutant larval CNS as assayed by quantitative RT-PCR, suggesting that trol neuroblasts are arrested in G1 due to lack of Cyclin E. Neither cyclin E nor E2F expression can phenocopy ana mutations, indicating that arrest caused by lack of Trol is different from Ana-mediated arrest.

Use of propensities of amino acids to the local structural environments to understand effect of substitution mutations on protein stability

Advances in site-directed mutagenesis and other genetic engineering techniques have made it possible to create novel proteins of interest. A challenging aspect of these studies is to understand the effect of substitution mutations on folding and stability of natural proteins. We present an analysis of protein structure data, available from the literature, for which substitution mutations have been made and changes in stability characteristics are reported. Amino acid structural environment parameters have been computed for a set of 304 non-homologous best resolved protein structures. The structural environment parameters were used to calculate each of the 20 amino acid propensities to a given structural environment. The observed increase or decrease in stability upon mutation was found to be correlated with the average residue structural environment propensity of wild-type residue versus mutant residue. The analysis presented here helps identification of less optimally placed residues in a given protein structure, and suggests possible substitution mutations to a residue with higher propensity to the corresponding local structural environment. We propose that such substitution mutations, suggested based on amino acid propensities to local structural environments, should bestow higher stability to the protein structure.

Localization of pontine PGO wave generation sites and their anatomical projections in the rat

A number of experimental and theoretical reports have suggested that the ponto-geniculo-occipital (PGO) wave-generating cells are involved in the generation of rapid eye movement (REM) sleep and REM sleep dependent cognitive functions. No studies to date have examined anatomical projections from PGO-generating cells to those brain structures involved in REM sleep generation and cognitive functions. In the present study, pontine PGO wave-generating sites were mapped by microinjecting carbachol in 74 sites of the rat brainstem. Those microinjections elicited PGO waves only when made in the dorsal part of the nucleus subcoeruleus of the pons. In six rats, the anterograde tracer biotinylated dextran amine (BDA) was microinjected into the physiologically identified cholinoceptive pontine PGO-generating site to identify brain structures receiving efferent projections from those PGO-generating sites. In all cases, small volume injections of BDA in the cholinoceptive pontine PGO-generating sites resulted in anterograde labeling of fibers and terminals in many regions of the brain. The most important output structures of those PGO-generating cells were the occipital cortex, entorhinal cortex, piriform cortex, amygdala, hippocampus, and many other thalamic, hypothalamic, and brainstem nuclei that participate in the generation of REM sleep. These findings provide anatomical evidence for the hypothesis that the PGO-generating cells in the pons could be involved in the generation of REM sleep. Since PGO-generating cells project to the entorhinal cortex, piriform cortex, amygdala, and hippocampus, these PGO-generating cells could also be involved in the modulation of cognitive functions.

Role of bone marrow and thymus secretory protein in maintaining immune homeostasis and haemopoiesis in control and malnourished mice

Injection of Salmonella typhi 'H' antigen was observed to produce a differential effect on bone marrow and thymus secretory profile depending upon the nutritional status of the host. The paracrine effect of Thy F1 (thymus fraction 1) was more significant (P < 0.01) than the autocrine effect of BIM (Bone marrow immunomodulator) in malnourished mice. BIM moreover, also had a paracrine effect on thymus irrespective of the nutritional status of the host. An improvement in neutrophil population (P < 0.01) and phagocytic myeloperoxidase activity (P < 0.01) was observed in BIM treated malnourished immuno-suppressed mice, whereas no appreciable change was observed by Thy F1. However, Thy F1 irrespective of the nutritional status of the host improved large lymphocyte population in circulation (P < 0.01). These findings indicate that both bone marrow and thymus play a major role in haemopoietic microenvironment of BDF (basal diet fed) control and malnourished mice.

Keratinocyte-specific retinoid regulation of human cellular retinoic acid binding protein-II (hCRABPII) gene promoter requires an evolutionarily conserved DR1 retinoic acid-responsive element

Transcription of the hCRABPII gene is retinoid inducible in human skin keratinocytes (KC) but, surprisingly, not in cultured cells. The promoter for the gene harbors three putative nuclear receptor binding sites: DR5, upstream of the transcription start site; DR1 (DR1d), distal to the site; and DR1 (DR1p), a proximal variant. DR1d, but not DR1p, is conserved between human and mouse. Although DR5 has been found to be a retinoid receptor target in COS-1 cells, the function of DR1 remains unknown. We examined the functions of these DR in retinoid regulation of the hCRABPII promoter in human KC. In reporter gene assays, no significant retinoid response was observed in the promoter in cultured KC; however, overexpression of retinoid receptor heterodimers RARgamma x RXRalpha restored the response. Gel supershift assays showed that endogenous RARgamma x RXRalpha levels are much lower in cultured KC than in skin in vivo. Ligand-binding assays showed that cultured KC contain only one-third of the level of retinoic acid receptor (RAR) and one-eighth of the level of retinoid X receptor found in KC in skin. Deletion of the DR1d or DR5 sites reduced retinoid-induced promoter activity by 63% and 27%, respectively. Isolated DR1d and DR5 sites, but not DR1p, efficiently bound RARgamma-RXRalpha and conferred RAR-selective retinoid responsiveness on a heterologous promoter. These data indicate that: (i) the previously reported lack of retinoid regulation of endogenous hCRABPII gene transcription in cultured KC is likely due to insufficient levels of RARgamma x RXRalpha, but not their cofactors; (ii) the conserved DR1d site is the major functional target in RARgamma x RXRalpha regulation of hCRABPII in KC; (iii) the DR1p site is nonfunctional due to its lack of affinity for RARgamma x RXRalpha, although its half-sites share high sequence homology with the consensus retinoid receptor-binding half-site.

Clonidine added to bupivacaine-epinephrine-sufentanil improves epidural analgesia during childbirth

BACKGROUND AND OBJECTIVES

A double-blind study was conducted to assess the efficacy and the side effects of a low dose of clonidine added to an epidural injection of bupivacaine and epinephrine, with or without sufentanil.

METHODS

One hundred healthy parturients (ASA 1) were randomly allocated into four groups according to the type of epidural analgesia administered. The bupivacaine/epinephrine (BE) group received a 10-mL standard injection of bupivacaine (B) 1.25 mg/mL and epinephrine (E) 1.25 microg/mL. In the bupivacaine/epinephrine/sufentanil (BES) group, 7.5 microg sufentanil (S) was added to the BE mixture. For the bupivacaine/ epinephrine/clonidine (BEC) group, 50 microg clonidine (C) was added to the BE mixture, whereas for the bupivacaine/epinephrine/sufentanil/clonidine (BESC) group, both sufentanil and clonidine were added to BE. Fetal heart rate was monitored by continuous cardiotocography. Duration of analgesia, method of delivery, and neonatal outcome (measured using APGAR score, peripheral oxygen saturation, and neurologic adaptive capacity score) and side effects of clonidine were observed. The parturients were routinely asked for their global appreciation of the epidural analgesia technique by visual analog score, 2 hours postpartum.

RESULTS

The overall quality and duration of analgesia were superior in the BESC group compared with the other groups, as was the global appreciation by the parturient. The frequency of side effects in the clonidine groups was comparable, with the exception of hypotension and sedation. Hypotension was easily treated by fluids or ephedrine and caused no fetal distress. The level of sedation was mild, and all parturients aroused immediately after verbal commands.

CONCLUSION

The addition of a low dose of clonidine to an epidural injection of bupivacaine with epinephrine and sufentanil provides better analgesia during labor, while keeping the side effects minimal and of minor clinical importance.

The tocolytic effect of catecholamines in the gravid rat uterus

Maternal catecholamines increase dramatically in labor because of pain and emotional stress. Because the uterus is richly endowed with both alpha- and beta-adrenergic receptors, catecholamines could alter uterine activity. We assessed the effect of clinically encountered concentrations of these catecholamines on uterine activity and modeled the effect of the abrupt reduction in circulating epinephrine that occurs during effective labor analgesia. Term pregnant rat uteri were excised, and cross-sectional rings were mounted for isometric force recording. Log concentration-response curves for epinephrine, norepinephrine, and their combination on uterine activity were constructed from 10(-12) to 10(-6) M. Catecholamine responses were repeated in the presence of phentolamine, an alpha-adrenergic blocker or propranolol, a beta-adrenergic blocker. The abilities of oxytocin and of washout of catecholamines to reverse catecholamine-induced changes in uterine activity were also assessed. Epinephrine caused dose-dependent reductions in uterine activity, blocked by propranolol. Epinephrine concentrations in the clinical range(10(-9) to 10(-8) M; 100-1000 pg/mL) decreased uterine activity to 49.6% +/- 6.6% (mean +/- SE) of control. Norepinephrine caused a dose-dependent increase in uterine activity, which was blocked by phentolamine. In the clinical range (10(-8) M), uterine activity was 139.2% +/- 13.40% of control. The combination of both catecholamines, however, was nearly as tocolytic as epinephrine alone. Oxytocin antagonized catecholamine-induced tocolysis, and washout of epinephrine or both catecholamines increased uterine activity. We conclude that mixed catecholamines are significantly tocolytic at concentrations encountered in laboring women. In this in vitro model, reduction in epinephrine concentration, comparable to that which occurs during effective analgesia, significantly increases uterine activity.

IMPLICATIONS

Maternal catecholamines increase in labor, but epinephrine decreases dramatically after regional analgesia. In this study, we found that norepinephrine and epinephrine together decrease uterine contractile activity and that decreased epinephrine causes significantly increased uterine activity.

Intrathecal ropivacaine for labor analgesia: a comparison with bupivacaine

Ropivacaine has less potential for central nervous system and cardiovascular toxicity than bupivacaine; in pregnant patients and volunteers, it produces less motor block in equianalgesic doses than bupivacaine. We compared two doses of intrathecal ropivacaine combined with sufentanil with a standard dose of intrathecal bupivacaine plus sufentanil for labor analgesia using a combined spinal-epidural (CSE) technique. In a prospective, randomized, double-blind fashion, 48 patients requesting labor analgesia received either 2.5 mg of intrathecal bupivacaine plus sufentanil 10 microg (B), 2 mg of intrathecal ropivacaine plus sufentanil 10 microg (R2), or 4 mg of intrathecal ropivacaine plus sufentanil 10 microg (R4). Duration of analgesia and side effects, such as motor block, pruritus, hypotension, ephedrine requirements and fetal bradycardia, were recorded. Duration of analgesia (mean +/- SD) was 79+/-30 min for R2, 98+/-19 min for R4, and 92+/-38 min for B (P = not significant). No differences in motor block or side effects were detected among the groups. We conclude that ropivacaine, when combined with sufentanil, is effective for providing CSE labor analgesia and offers no advantage over bupivacaine in the studied doses.

IMPLICATIONS

In this study, we compared a standard dose of intrathecal bupivacaine with sufentanil for combined spinal epidural analgesia with two doses of the new local anesthetic ropivacaine. Both local anesthetics provided similar labor analgesia duration with equivalent side effect profiles in the doses studied.

Intrathecal sufentanil and epidural bupivacaine for labor analgesia: dose-response of individual agents and in combination

BACKGROUNDS AND OBJECTIVES

Combinations of local anesthetics and opioids are frequently used during spinal and epidural analgesia for the relief of labor pain. This combination allows for a dose-sparing effect which may reduce potential side effects or toxicity. The precise nature of the interaction between opioids and local anesthetics in the clinical setting, i.e., additivity versus synergism, has not been established. This trial was designed to utilize a validated technique of analysis of drug interactions, isobolography, to investigate this interaction.

METHODS

One hundred healthy laboring patients at term receiving a combined spinal and epidural technique were divided into nine groups as follows: intrathecal sufentanil 2, 5, or 10 microg (2 mL volume) and epidural saline (10 mL); epidural bupivacaine 5, 12.5, or 25 mg and intrathecal saline (2 mL volume); or combination of l, 2.5, and 5 microg intrathecal sufentanil plus 2.5, 6.25, or 12.5 mg epidural bupivacaine, using similar volumes, respectively. All drugs were administered in a randomized, double-blind fashion. Pain relief scores were assessed 20 minutes after drug injection, and isobolographic analysis was utilized to determine the nature of the interaction.

RESULTS

The ED50 of intrathecal sufentanil alone was 2.3 microg (95% CI 1.7-3.2), and the ED50 for epidural bupivacaine was 24 mg (95% CI 12-50). The combined sufentanil and bupivacaine fractional dose ED50 (in fractions of the single-dose ED50 values) was found to be approximately one-third and one-tenth of the single drug fractional dose, respectively: sufentanil 0.85 microg (0.36) and bupivacaine 2.2 mg (0.09). The duration of analgesia was nearly equivalent in all sufentanil-alone groups (83, 102, and 99 minutes); a dose-response effect was more apparent in the bupivacaine group (35, 42, and 74 minutes; P = .006) and the combination group (60, 79, 101 minutes; P = .028). Isobolography showed the combination dose to lie well within the area of synergism; however, the 95% confidence limits cross the line of additivity thus a pure additive interaction cannot be excluded.

CONCLUSIONS

Markedly reduced doses of these drugs in combination can be used to provide adequate analgesia during labor compared with either single drug alone.

Developmental selection of var gene expression in Plasmodium falciparum

The protozoan Plasmodium falciparum causes lethal malaria. Adhesion of erythrocytes infected with P. falciparum to vascular endothelium and to uninfected red blood cells (rosetting) may be involved in the pathogenesis of severe malaria. The binding is mediated by the antigenically variant erythrocyte-membrane-protein-1 (PfEMP-1), which is encoded by members of the P. falciparum var gene family. The control of expression and switching of var genes seems to lack resemblance to mechanisms operating in variant gene families of other microbial pathogens. Here we show that multiple, distinct var gene transcripts (about 24 or more) can be detected by reverse transcription and polymerase chain reaction in bulk cultures of the rosetting parasite FCR3S1.2, despite the adhesive homogeneity of the cultures. We also detected several var transcripts in single erythrocytes infected with a ring-stage parasite of FCR3S1.2, and found that different var genes are transcribed simultaneously from several chromosomes in the same cell. In contrast, we detected only one var transcript, FCR3S1.2 var-1, which encodes the rosetting PfEMP-1 protein, in individual rosette-adhesive trophozoite-infected cells, and we found only one PfEMP-1 type at the erythrocyte surface by labelling with 125iodine and immunoprecipitation. We conclude that a single P. falciparum parasite simultaneously transcribes multiple var genes but, through a developmentally regulated process, selects only one PfEMP-1 to reach the surface of the host cell.

Thrombopoietin in normal pregnancy and preeclampsia

OBJECTIVE

In normal pregnancy and pregnancies complicated by preeclampsia it has been demonstrated that there is increased activation of platelets and the clotting and fibrinolytic system. We measured plasma levels of thrombopoietin, a major regulator of platelet production in these conditions.

STUDY DESIGN

We compared the thrombopoietin plasma levels of healthy term pregnant patients (n = 21) with those of healthy nonpregnant controls (n = 17), as well as patients with severe preeclampsia (n = 8) and the hemolysis, elevated liver enzymes, low platelets syndrome (n = 6).

RESULTS

Thrombopoietin levels in normal pregnant patients and pregnancies complicated by the hemolysis, elevated liver enzymes, low platelets syndrome were statistically significantly higher than thrombopoietin levels in nonpregnant controls. Data were analyzed with the Kruskal-Wallis one-way analysis of variance by ranks.

CONCLUSIONS

This study is the first to report thrombopoietin levels in pregnancy. Thrombopoietin levels are significantly greater in pregnant patients and in pregnancies complicated by the hemolysis, elevated liver enzymes, low platelets syndrome compared with nonpregnant controls.