Low-dose Treatment Regimen Research Articles

Gastrointestinal safety evaluation of semaglutide for the treatment of type 2 diabetes mellitus: A meta-analysis.

Semaglutide, as an innovative weekly formulation, has attracted much attention. Nevertheless, the predominant occurrence of gastrointestinal adverse events (GIAEs) poses a noteworthy challenge linked to the use of this medication, substantially affecting its clinical applicability and the overall well-being of patients. Therefore, this systematic review aims to comprehensively discuss the GIAEs, providing a basis for clinical therapeutic decisions. We systematically searched 4 independent databases for randomized controlled trials investigating the application of semaglutide in managing type 2 diabetes mellitus. The search period spanned from the inception of the databases to December 2023. We conducted a comprehensive meta-analysis, employing Review Manager 5.4.1 software, to systematically analyze and evaluate potential biases. Our primary emphasis was on assessing the gastrointestinal safety profile of semaglutide. The outcomes unveiled a noteworthy rise in the collective occurrence of GIAEs across all dosage groups of semaglutide in comparison with the control group (P < .05). Upon further analysis, it was observed that semaglutide showed a heightened occurrence of GIAEs in contrast to the placebo. However, statistically significant distinction was not observed when compared to the reduction of conventional doses or the transition to other types of glucagon-like peptide-1 receptor agonist. Additionally, an extended treatment duration with semaglutide (>30 weeks) demonstrated an association with a certain degree of decrease in the incidence of gastrointestinal events. Funnel plot assessment for publication bias demonstrated high-quality inclusion of studies with no apparent publication bias. The frequency of GIAEs in using semaglutide was observed to be elevated in comparison to the control group. However, it was comparable to other glucagon-like peptide-1 receptor agonist or low-dose treatment regimens. Additionally, an extended treatment duration played a role in decreasing the frequency of GIAEs. These findings provide valuable insights for clinical practice. Nonetheless, further research is crucial to explore supplementary data indicators, informing clinical practices and better serving the interests of patients.

Risk of Developing Hypertension in Atopic Dermatitis Patients Receiving Long-term and Low-dose Cyclosporine: A Nationwide Population-based Cohort Study.

Cyclosporine (CS) is a first-line immunosuppressive agent used to manage moderate to severe atopic dermatitis (AD). To date, the risk of developing hypertension associated with the long-term use of low-dose CS in AD patients is understudied. To determine the cumulative dose-dependent effect of CS on the risk of developing hypertension in patients with AD. A nationwide population-based retrospective cohort with 1,844,009 AD patients was built from the Korean National Health Insurance System database from 2005 to 2009. A Cox proportional-hazard regression analysis was performed according to patients' CS treatment history adjusted for potential confounders. Current use of CS was associated with an increased risk of developing hypertension (adjusted hazard ratio, 4.442; 95% confidence interval, 3.761-5.247). Among the current CS users, a higher cumulative dose of CS (≥39,725 mg) or longer cumulative use of CS (≥182 days), was significantly associated with an increased risk of developing hypertension. The incidence of CS-associated hypertension is very low when using low-dose treatment regimens for AD. However, the current use or a high cumulative dose of CS for treating patients with AD increases the risk of developing hypertension. Precaution is needed when prescribing CS for long-term treatment of AD.

Low-dose antenatal betamethasone treatment achieves preterm lung maturation equivalent to that of the World Health Organization dexamethasone regimen but with reduced endocrine disruption in a sheep model of pregnancy

The intramuscular administration of antenatal steroids to women at risk of preterm delivery achieves high maternal and fetal plasma steroid concentrations, which are associated with adverse effects and may reduce treatment efficacy. We have demonstrated that antenatal steroid efficacy is independent of peak maternofetal steroid levels once exposure is maintained above a low threshold. This study aimed to test, using a sheep model of pregnancy, whether the low-dose antenatal steroid regimen proposed as part of the Antenatal Corticosteroids for Improving Outcomes in Preterm Newborns trial would achieve preterm lung maturation equivalent to that of the existing World Health Organization dexamethasone treatment regimen, but with reduced risk of adverse outcomes. Following ethical review and approval, date-mated ewes with single fetuses received intramuscular injections of either (1) four 6-mg maternal intramuscular injections of dexamethasone phosphate every 12 hours (n=22), (2) 4 2-mg maternal intramuscular injections of betamethasone phosphate every 12 hours (n=21), or (3) 4 2-mL maternal intramuscular injections of saline every 12 hours (n=16). Of note, 48 hours after first injection, (124±1 day), lambs were delivered, ventilated for 30 minutes, and euthanized for sampling. Arterial blood gas, respiratory, hematological, and biochemical data were analyzed for between-group differences with analysis of variance according to distribution and variance, with P<.05 taken as significant. After 30 minutes of ventilation, lambs from both steroid-treated groups had significant and equivalent improvements in lung function relative to saline control (P<.05). There was no significant difference in arterial blood pH, pO2, pCO2, lung compliance, ventilator efficiency index, or lung volume at necropsy with a static pressure of 40 cmH2O. The messenger RNA expression of surfactant protein (Sp)a, Spb, Spc, Spd, aquaporin (Aqp)1, Aqp5, and sodium channel epithelial 1 subunit beta (Scnn1b) was equivalent between both steroid groups. Maternal and fetal plasma neutrophil, glucose, and fetal plasma C-peptide levels were significantly elevated in the dexamethasone group, relative to the betamethasone group. Fetal plasma insulin-like growth factor 1 was significantly reduced in the dexamethasone group compared with the betamethasone group (P<0.05). Fetal adrenocorticotropic hormone (r=0.53), maternal glucose value (r=-0.52), and fetal glucose values (r=-0.42) were correlated with maternal weight in the betamethasone group (P<.05), whereas fetal pCO2 and pO2 were not correlated. There was no significant difference between male and female lamb outcomes in any groups for any of the items evaluated. This study reported that in preterm lambs, a low-dose treatment regimen of 8 mg betamethasone achieves lung maturation equivalent to that of a 24-mg dexamethasone-based regimen, but with smaller perturbations to the maternofetal hypothalamic-pituitary-adrenal axis. These data suggested that given steroid pharmacokinetic differences between sheep and humans, a betamethasone dose of 2 mg may remain above the minimum dose necessary for robust maturation of the preterm lung. Maternal weight-adjusted betamethasone doses might also be a key to reducing perturbations to the maternofetal hypothalamic-pituitary-adrenal axis.

Abstract 3095: Breaking the crosstalk of the cellular tumorigenic network in NSCLC by a highly effective drug combination

Abstract Background: Non-small cell lung cancer (NSCLC) is commonly diagnosed at advanced stages with limited treatment options particularly in tumors without targetable driver mutations. Methods: Considering previously published criteria for selecting drug combinations for overcoming drug resistances1, we have established a low dose combination therapy with cabozantinib, afatinib, etoricoxib and plerixafor. Utilizing NSCLC patient-derived xenograft (PDX) models we aimed to use this drug regimen to disrupt paracrine substitutional signaling within the tumorigenic network in order to circumvent pre-existing and adaptive drug resistances. In contrast to daily dosing for respective monotherapies the low dose treatment was paused every five days for two days. Result: All PDX tumors treated, including highly therapy-resistant adeno- and squamous cell carcinomas without identifiable driver mutations, were completely suppressed by this drug regimen leading to an Objective Response Rate of 81% and a Clinical Benefit Rate of 100%. After treatment discontinuation growth suppression remained until the end of the follow-up period with only slight increase in tumor growth. The application and the safety profile of this low dose therapy regimen was well manageable and without pronounced side effects in this pre-clinical setting. Discussion: For the first time we show that simultaneous inhibition of pathways forming the cellular tumorigenic network in NSCLC tumors is highly effective and overcomes drug resistances for monotherapies. All of the drugs used in this combination regimen are approved for different indications and therefore readily available. Conclusion: Our results emphatically encourage a setup for a clinical study in advanced stage NSCLC patients without targetable driver mutations combining the drugs cabozantinib, afatinib, plerixafor and etoricoxib in a low dose treatment regimen as novel therapy strategy. Indication of Source: 1. Langhammer S and Scheerer J. Oncotarget 8, 43555-43570 (2017). Citation Format: Dennis Gürgen, Theresia Conrad, Michael Becker, Susanne Sebens, Christoph Röcken, Jens Hoffmann, Stefan Langhammer. Breaking the crosstalk of the cellular tumorigenic network in NSCLC by a highly effective drug combination [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3095.

Continuous but not pulsed low-dose fetal betamethasone exposures extend the durability of antenatal steroid therapy.

Antenatal steroid (ANS) therapy is the standard care for women at imminent risk of preterm labor. Despite extensive and long-standing use, 40%-50% of babies exposed antenatally to steroids do not derive benefit; remaining undelivered 7 days or more after ANS treatment is associated with a lack of treatment benefit and increased risk of harm. We used a pregnant sheep model to evaluate the impact of continuous versus pulsed ANS treatments on fetal lung maturation at an extended, 8-day treatment to delivery interval. Continuous low-dose ANS treatments for more than 72 h in duration improved fetal lung maturation at 8 days after treatment initiation. If fetal ANS exposure was interrupted, the beneficial ANS effect was lost. Truncated treatments, including that simulating the current clinical treatment regimen, did not improve lung function. Variable fetal lung maturation was correlated to the amount of saturated phosphatidylcholine present in the lung fluid. These data demonstrate that 1) the durability of ANS therapy may be enhanced by employing an extended, low-dose treatment regimen by reducing total dose and 2) interrupting the continuity of fetal exposure by allowing it to fall below a minimal threshold was associated with comparably poor functional maturation of the preterm ovine lung.

No difference in patient compliance between full-strength versus low-dose aspirin for VTE prophylaxis following total hip and total knee replacement.

The utilization of aspirin for VTE prophylaxis following TJA has increased due to updated clinical practice guidelines. Aspirin is the only approved VTE prophylaxis medication that does not require a prescription, but adherence and tolerance remain unknown. We hypothesized decreased patient compliance utilizing full-strength 325mg aspirin twice daily following TJA when compared to low-dose 81mg twice daily. We also investigated the reasons why patients may elect to stop the medication earlier than 28days. A consecutive series of patients undergoing primary total hip or knee arthroplasty utilizing 325 or 81mg of EC aspirin twice daily for 4weeks were surveyed to determine compliance with use and any adverse events related to the medication. Fisher's exact testwas used to determine statistical significance. 404 patients were enrolled with 199 patients prescribed the 325mg regimen. Fifty-two patients who were prescribed 325mg missed a dose versus 51 patients who were prescribed 81mg (p = 0.082). No significant difference in the frequency of missed doses (missing < 5 doses, 5-10 doses, > 10 doses) between the treatment regimens (p = 0.78, 0.39 and 0.83, respectively). Most commonly cited reason for stopping aspirin in both treatment groups was gastrointestinal issues (10.5% and 7%, respectively). By surveying patients on their use of aspirin we find no difference in adherence between full-strength and low-dose treatment regimens. Additionally, we have a better understanding of the reasons for noncompliance as GI upset was a relatively common complaint with both doses.

An 1H NMR study of the cytarabine degradation in clinical conditions to avoid drug waste, decrease therapy costs and improve patient compliance in acute leukemia.

Cytarabine, the 4-amino-1-(β-D-arabinofuranosyl)-2(1H)-pyrimidinone, (ARA-C) is an antimetabolite cytidine analogue used worldwide as key drug in the management of leukaemia. As specified in the manufacturers’ instructions, once the components—sterile water and cytarabine powder—are unpackaged and mixed, the solution begins to degrade after 6 hours at room temperature and 12 hours at 4°C. To evaluate how to avoid wasting the drug in short-term, low-dose treatment regimens, the reconstituted samples, stored at 25°C and 4°C, were analyzed every day of the test week by reversed-phase HPLC and high-field NMR spectroscopy. All the samples remained unchanged for the entire week, which corresponds to the time required to administer the entire commercial drug package during low-dose therapeutic regimens. The drug solution was stored in a glass container at 4°C in an ordinary freezer and drawn with sterile plastic syringes; during this period, no bacterial or fungal contamination was observed. Our findings show that an cytarabine solution prepared and stored in the original vials retains its efficacy and safety and can, therefore, be divided into small doses to be administered over more days, thus avoiding unnecessary expensive and harmful waste of the drug preparation. Moreover, patients who require daily administration of the drug could undergo the infusion at home without need to go to hospital. The stability of the aliquots would help decrease hospitalization costs.

Interactions of liposomes carrying lipophilic prodrugs in the bilayer with blood plasma proteins

Interactions of 100-nm liposomes prepared from egg yolk phosphatidylcholine and baker’s yeast phosphatidylinositol carrying diglyceride ester conjugates of melphalan (Mlph-liposomes) and methotrexate (MTX-liposomes) in the bilayer with blood plasma proteins were studied with Western blotting. Earlier hemocompatibility tests have demonstrated that the liposomes did not affect main blood cells, but MTX-liposomes, and not Mlph-liposomes, induced complement (C) activation in vitro. Here, we show that introduction of polyethylene glycol conjugate (instead of phosphatidylinositol as a stabilizing lipid) or a targeting carbohydrate conjugate has little effect on interaction of Mlph-liposomes with major C components and apolipoproteins, as well as the total protein binding ability of the liposomes. Liposomes loaded with Mlph prodrug did not trigger fragmentation of C3 protein, the central component of the complement, while MTX-liposomes did so, which agrees with our previous findings. Analysis of MTX-liposome binding with C3 protein and its fragments, regulatory C proteins, and immunoglobulins allowed for the conclusion that MTX-liposomes activate complement via the alternative activation pathway. As shown earlier, the decrease in the prodrug concentration in the bilayer to the level corresponding to MTX low-dose treatment regimen allows avoiding C activation.

Targeted antisense radiotherapy and dose fractionation using a 177Lu-labeled anti-bcl-2 peptide nucleic acid-peptide conjugate

IntroductionThe overall goal of these studies was to test the hypothesis that simultaneous down-regulation of a tumor survival gene and delivery of internally emitted cytotoxic radiation will be more effective than either treatment modality alone. The objectives were to evaluate the therapeutic efficacy of a 177Lu-labeled anti-bcl-2-PNA-Tyr3-octreotate antisense conjugate in a mouse model bearing human non-Hodgkin’s lymphoma (NHL) tumor xenografts and to optimize targeted antisense radiotherapy by dose fractionation. MethodsIn the initial therapy studies, tumor-bearing mice were given saline, nonradioactive DOTA-anti-bcl-2-PNA-Tyr3-octreotate, 177Lu-DOTA-Tyr3-octreotate, 177Lu-DOTA-PNA-peptide alone, or 177Lu-DOTA-PNA-peptide followed by a chase dose of nonradioactive PNA-peptide. The MTD of 177Lu-DOTA-anti-bcl-2-PNA-Tyr3-octreotate was then determined. Subsequently single dose MTD and four weekly fractionated doses were directly compared, followed by histopathologic evaluation. ResultsAntisense radiotherapy using 4.44MBq of the 177Lu-DOTA-PNA-peptide followed by nonradioactive PNA-peptide was significantly more effective than other low dose treatment regimens. A dose of 18.5MBq of 177Lu-DOTA-PNA-peptide was determined to be the approximate maximum tolerated dose (MTD). The median times to progression to a 1cm3 tumor volume were 32 and 49days for single dose MTD and fractionated dose (4×4.63MBq) groups, respectively. Histopathology revealed metastases in the single dose groups, but not in the dose fractionation group. ConclusionsTargeted antisense radiotherapy using 177Lu-DOTA-anti-bcl-2-PNA-Tyr3-octreotate and DOTA-PNA-peptide conjugate effectively inhibited tumor progression in a mouse model of NHL. Furthermore, a dose fractionation regimen had a significant advantage over a single high dose, in terms of tumor growth inhibition and prevention of metastasis. Advances in knowledge and implications for patient careDown-regulating bcl-2, an anti-apoptotic proto-oncogene, is a mechanism to reverse chemotherapy resistance or failure in humans with NHL. We have developed a 177Lu-DOTA-anti-bcl-2-PNA-Tyr3-octreotate conjugate for targeted antisense radiotherapy, in which down-regulation of bcl-2 and delivery of cytotoxic radiation occur simultaneously. Our previous studies have shown highly specific inhibition of bcl-2 protein, additive in vitro cytotoxic effects on human lymphoma cells, and favorable biodistribution and dosimetric properties. Lutetium-177 targeted antisense radiotherapy demonstrates a significant advantage over conventional 177Lu-peptide receptor radionuclide therapy in a mouse model of NHL. Our preclinical studies identified an effective combination of antisense and radionuclide therapy, with the goal of future clinical trials in patients.

Gender‐Specific Differences in Susceptibility to Low‐Dose Methadone‐Associated QTc Prolongation in Patients with Heroin Dependence

Methadone is associated with QTc prolongation and sudden death in susceptible patients. We sought to investigate whether there is a gender-based difference in susceptibility to methadone-associated QTc prolongation in heroin-dependent patients receiving a low-dose treatment regimen. A cross-sectional assessment of dose and gender effects was performed in 283 patients (229 males, 54 females) who received a 12-lead ECG for QTc measurement 59 days (interquartile range: 36-288 days) after methadone treatment. To determine the effects of methadone over time, a subset of 150 participants (126 men, 24 women) who underwent a 12-lead ECG before and 37 days (interquartile range: 32-44 days) after methadone treatment were selected. In the cross-sectional study, a significant dose-dependent interaction between methadone and QTc (r = 0.201, P = 0.0007) was observed in individuals receiving a median methadone dose of 40 mg/day (interquartile range: 30-60 mg/day). The methadone-QTc correlation was significant in males (r = 0.210, P = 0.0014) but not in females (r = 0.164, P = 0.2363). The longitudinal assessment of methadone's effects over a 6-month period showed that 60.7% of individuals experienced an increase in QTc compared to baseline data. The adjusted QTc significantly increased from 418.5 to 426.9 milliseconds in males (P < 0.0001), compared to an insignificant change in females (437.7 milliseconds vs 441.1 milliseconds, P = 0.468). Low-dose methadone therapy shows dose-dependent QTc prolongation and is associated with significant QTc lengthening within 6 months of treatment initiation. Men are more susceptible than women to low-dose methadone-associated QTc prolongation.

Health-related quality of life in patients with systemic lupus erythematosus and proliferative lupus nephritis

This study investigated the influence of two different treatments for a kidney inflammation (i.e. proliferative lupus nephritis) on health-related quality of life (HRQoL) in patients with the chronic auto-immune disease systemic lupus erythematosus (SLE). One treatment protocol, the National Institutes of Health (NIH) protocol, was characterized by a high dose of cyclophosphamide (CYC, an immunosuppressive drug), and the second treatment, the Euro-Lupus protocol, involved a low-dose CYC. Thirty-two SLE patients were included based on the received treatment for an episode of proliferative lupus nephritis, according to either the Euro-Lupus or the NIH protocol. The two groups were compared on HRQoL as measured by the SF-36 and the SLE Symptom Checklist (SSC). The Euro-Lupus group (N = 16) tended to show a higher HRQoL than the NIH group (N = 16) on four of seven scales of the SF-36. In addition, the Euro-Lupus group experienced less burden from nausea or vomiting than the NIH group as assessed by the SSC. Fatigue was the most disturbing symptom in both groups. The most burdensome aspects of treatment were related to chemotherapy (55.2%) and use of prednisone (34.5%). Patients with a low HRQoL and high levels of fatigue were more likely to have low levels of serum complement C4 (i.e. elevated immune activity). In conclusion, patients who are treated according to the Euro-Lupus protocol may experience a higher HRQoL than patients who receive the NIH treatment. However, chemotherapy remains burdensome in the low-dose treatment regimen. Potential interventions to further enhance the HRQoL in SLE patients with proliferative lupus nephritis are discussed.

Low dose, short-term rivastigmine administration does not affect neurocognition in methamphetamine dependent individuals

Neurocognitive impairment is a well-documented consequence of methamphetamine addiction. Not surprising, methamphetamine-associated neurocognitive impairment has been identified as an important target of treatment. Thus, this study sought to determine whether rivastigmine, an acetylcholinesterase inhibitor and cognition enhancing agent, could improve neurocognitive performance in a sample of long-term, high-dose methamphetamine addicts who were not seeking treatment at the time of enrollment in the study. This double-blind, placebo-controlled study evaluated whether a daily dose 0, 3, or 6mg of rivastigmine, administered over six consecutive days, would enhance performance on measures of attention/information processing speed, episodic memory, and executive/frontal lobe functioning relative to test performance at baseline. The results revealed that rivastigmine did not alter neurocognition in this cohort. There are a number of factors that may have mitigated the effects of rivastigmine in this particular study, including especially the short-term, low-dose treatment regimen utilized. The negative findings notwithstanding, the study serves as a springboard for future investigations that will examine whether other medications can alter neurocognition in methamphetamine dependent study participants.

Evaluation of the toxicity of Adonis aestivalis in sheep

To determine the toxicity of Adonis aestivalis (adonis) in sheep, adult Suffolk ewes were administered 1 per cent bodyweight adonis via surgically placed rumen cannulas in an acute, high-dose toxicity...

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Efficacy of Short-Course, Low-Dose Corticosteroid Therapy for Acute Pulmonary Sarcoidosis Exacerbations

BackgroundAlthough corticosteroids are the drug of choice for acute exacerbations of pulmonary sarcoidosis, the dose and duration of therapy is not standardized. We reviewed the short-term treatment outcome (median duration=21days) of 36 patients with acute exacerbations of pulmonary sarcoidosis using low-dose corticosteroid therapy (20mg or less of daily prednisone equivalent). To the best of our knowledge, this is the shortest period of time over which the treatment of pulmonary sarcoidosis with corticosteroids has been assessed. MethodsPatients were identified retrospectively from an institution-approved database. Patient symptoms and spirometry were obtained from chart review. Additional clinical data were obtained from chart and database review. ResultsFollow-up visits occurred a median of 21days after the date of the exacerbation (mean 25±3 standard error of mean). The average prednisone dose was 19mg±0.4 standard error of mean. Patients had significant improvement in spirometry on this low-dose treatment regimen by the time of their short-term follow-up (forced vital capacity percent predicted improved from 68 to 82 [P<0.0001] and was not significantly different from baseline; forced expiratory volume in 1second percent predicted improved from 57 to 72 [P<0.0001] and was not significantly different from baseline). Pulmonary symptoms also improved. ConclusionsTreatment of acute exacerbations of pulmonary sarcoidosis with 20mg prednisone for a median of 21days improved spirometry back to baseline and improved clinical symptoms. These data suggest that this corticosteroid dose can be safely used initially, and an attempt at tapering can be considered within the first month.

Biological effects of short-term or prolonged administration of 9-[2-(phosphonomethoxy)propyl]adenine (tenofovir) to newborn and infant rhesus macaques.

The reverse transcriptase inhibitor 9-[2-(phosphonomethoxy)propyl]adenine (PMPA; tenofovir) was previously found to offer strong prophylactic and therapeutic benefits in an infant macaque model of pediatric human immunodeficiency virus (HIV) infection. We now summarize the toxicity and safety of PMPA in these studies. When a range of PMPA doses (4 to 30 mg/kg of body weight administered subcutaneously once daily) was administered to 39 infant macaques for a short period of time (range, 1 day to 12 weeks), no adverse effects on their health or growth were observed; this included a subset of 12 animals which were monitored for more than 2 years. In contrast, daily administration of a high dose of PMPA (30 mg/kg subcutaneously) for prolonged periods of time (>8 to 21 months) to 13 animals resulted in a Fanconi-like syndrome (proximal renal tubular disorder) with glucosuria, aminoaciduria, hypophosphatemia, growth restriction, bone pathology (osteomalacia), and reduced clearance of PMPA. The adverse effects were reversible or were alleviated following either complete withdrawal of PMPA treatment or reduction of the daily regimen from 30 mg/kg to 2.5 to 10 mg/kg subcutaneously. Finally, to evaluate the safety of a prolonged low-dose treatment regimen, two newborn macaques were started on a 10-mg/kg/day subcutaneous regimen; these animals are healthy and have normal bone density and growth after 5 years of daily treatment. In conclusion, our findings suggest that chronic daily administration of a high dose of PMPA results in adverse effects on kidney and bone, while short-term administration of relatively high doses and prolonged low-dose administration are safe.

Immunotherapy of experimental bladder cancer with recombinant BCG expressing interferon-gamma.

One of the most potent immunotherapies presently used is the application of Bacillus Calmette Guérin (BCG) to prevent recurrences of superficial bladder cancer. Despite its successful use, nonresponders and certain side effects remain a major obstacle. Therefore, current studies aim at developing recombinant BCG (rBCG) strains to further improve the effectiveness of the therapy. In BCG-treated patients a strong local induction of Th1-like cytokines was observed. For this reason rBCG-strains secreting Th1-like cytokines might be potentially useful agents to improve this type of immunotherapy. Because we previously demonstrated the essential role of IFNgamma in BCG-induced antitumor responses, in this study a rBCG strain secreting murine IFNgamma (rBCG-IFNgamma) was generated and tested for its immunostimulatory capacity in several in vitro and in vivo test systems. In vitro rBCG-IFNgamma specifically up-regulated expression of MHC class I molecules on a murine bladder cancer cell line (MB49), compared to the rBCG control strain (transfected with an empty vector). In a murine model of experimental bladder cancer, intravesical instillation of rBCG-IFNgamma resulted in an enhanced recruitment of CD4+ T-cells into the bladder and further induced the local expression of IL-2 and IL-4 cytokines (mRNA) compared to control rBCG. With a low-dose treatment regimen for murine orthotopic bladder cancer, rBCG-IFNgamma significantly prolonged survival, whereas the therapeutic effect of wild-type control BCG did not reach statistical significance. We conclude that this recombinant BCG strain has enhanced immunostimulatory potential and might offer new opportunities in the treatment of bladder cancer.

The induction of parturition in the bitch using sodium cloprostenol

The objectives of this studies were to determine a continuous low-dose treatment regimen for the administration of sodium cloprostenol to the bitch that did not cause polydipsia, and whether this treatment would induce normal and timed parturition in bitches during late pregnancy. Non-pregnant greyhound bitches (n = 18) received sodium cloprostenol subcutaneously, via a mimosmotic pump, at dose rates of 0 875 to 4 5 μg/kg/24 h, for 7 days (Days 0 to 7) Daily water intake was measured from Day −2 to Day 9 Polydipsia was observed in bitches treated with the higher dose rates but not in bitches treated with the lowest dose rate of 0.875 μg/kg/24 h In the second experiment, pregnant greyhound bitches received sodium cloprostenol at dose rates of 1 (n = 4), 2 (n = 1) and 3 μg/kg/24 h (n = 1), on Day 57 of pregnancy. Polydipsia was observed in bitches treated at the higher dose rates of 2 and 3 μg/kg/24 h, but not in the bitches treated at the lower dose rate of 1 μg/kg/24 h. These treatments resulted in the successful induction of parturition Parturition was associated with a decrease in plasma progesterone concentrations, a reduction in body temperature, and an increase in plasma concentrations of 13,14-dihydro-15-keto prostaglandin F 2α The first puppy was born 37.7±2.9 h after the start of treatment (range 28 to 46 h). The duration of whelping was approximately 157±2.2 h (range 10 to 24 h) The litter size was 9 2±0 8 pups (range 6 to 12 pups), and the puppy survival rate was 6.0±0.8 per litter (range 4 to 9 pups). This study demonstrated that the administration of sodium cloprostenol in continuous low dose for 24 h is an effective treatment for the induction of parturition in bitches during late pregnancy. This treatment resulted in the birth of healthy pups, with minimal or no side effects to the bitch.

Antibiotic resistance in Neisseria meningitidis.

Penicillin has long been recognized as the antibiotic of choice for treatment of meningococcal infections, but clinicians have recently become concerned about the susceptibility of meningococci to penicillin and other antibiotics used in the management of meningococcal disease. Strains relatively resistant to penicillin (minimum inhibitory concentrations ranging from 0.1 mg/L to 1.28 mg/L) have been reported from a large number of countries, although the frequency with which such isolates are found varies widely. The mechanism of relative resistance to penicillin involves, at least in part, the production of altered forms of one of the penicillin-binding proteins. Although treatment with penicillin is still effective against these relatively resistant strains, there is evidence that low-dose treatment regimens can fail. beta-Lactamase production in meningococci is extremely rare but has been reported, and this finding is of great concern. Resistance to sulfonamides and rifampin is of particular concern in regard to the management of contacts of patients with meningococcal disease.

Termination of early gestation with the anti-progestin steroid RU 486: Medium versus low dose

RU 486 is a synthetic steroid which has antiprogesterone and antiglucocorticoid activity. In order to determine the optimal dosage of this drug to terminate early pregnancy, we treated 106 healthy women with normal pregnancies by real time ultrasound examination whose gestational duration was less than 49 days from onset of last menses with either a medium or low dose treatment regimen. A total of 66 patients received the medium dose regimen (100 mg/day × 7 days). Another 10 patients received ergonovine (0.2 mg/day × 6 doses) on Day 4 of the same RU 486 treatment regimen. In the first group, 48 (73%) aborted successfully and, of the second group, 6 (60%) aborted. Eighty percent of the subjects in this group of 76 patients reported side effects of nausea and vomiting, heavy bleeding, severe menstrual cramps or headache. All these side effects were successfully treated with analgesic and antiemetic medication. The remaining 30 subjects were treated with a low dose regimen (50 mg/day × 7 days). Of these 30, 15 (50%) aborted; this incidence was significantly less (p < 0.05). Following the medium dose treatment regimen, the AM cortisol levels were significantly elevated on treatment Days 4 and 8, as compared to baseline ( p < 0.001), although the mean levels were still within the normal range. With the low dose, there was a non-significant rise in AM cortisol values. Thus the rise in cortisol was significantly greater in the former group than the latter (p < 0.05). With the medium dose regimen, the women who aborted had significantly lower (p < 0.05) pretreatment mean B-HCG and progesterone levels than the group that failed to abort. Mean serum levels of RU 486 were not signficantly different between the group who aborted and those who did not. RU 486 is a promising agent for termination of early pregnancy.