beta-lactam derivatives as enzyme inhibitors: carboxy peptidyl derivatives of (S)-4-oxoazetidine-2-carboxylate as peptidomimetics

4-Oxoazetidine-2-carboxylic acid, protected at the nitrogen by silyl groups, was coupled with amino acid and oligopeptide esters. Desilylation and deprotection of the amino acid residues yielded the free beta-lactam peptides. Structure and properties were elucidated by spectroscopic methods and discussed. Some selected compounds were tested as fibrinogen inhibitors and for thrombocyte aggregation. None of the compounds showed any activity up to a concentration of 10(-5) Mol/l. Some other compounds exhibited a weak inhibitory activity against elastase (PPE).

Parental medical neglect in the treatment of adolescents with anorexia nervosa

OBJECTIVE

Although childhood sexual abuse has been a frequent focus of research on eating disorders, other forms of maltreatment have been less commonly reported. Parental medical neglect is examined in this study as having serious consequences for the treatment and prognosis of patients with anorexia nervosa.

METHOD

Two case studies illustrate parental interference with treatment in which Child Protective Services (CPS) had to be involved in compliance with state law. Two adolescent females who were admitted for treatment for anorexia nervosa are presented.

RESULTS

In both cases, the parents refused to comply with the recommendations of the treatment team, placing their children's health in jeopardy. In compliance with reporting guidelines, CPS was notified in both cases.

CONCLUSIONS

Clinicians who treat minors with anorexia nervosa must consider parental compliance with treatment. Indications for the involvement of CPS are outlined. Optimally, this notification can ensure that the patient and family receive the requisite treatment.

Rapid improvement of nitric oxide bioavailability after lipid-lowering therapy with cerivastatin within two weeks

OBJECTIVES

We investigated whether improvement of endothelial dysfunction in hypercholesterolemia can be achieved with short-term lipid-lowering therapy.

BACKGROUND

Impaired endothelium-dependent vasodilation plays a pivotal role in the pathogenesis of atherosclerosis and acute coronary syndromes.

METHODS

In a randomized, double-blind, placebo-controlled trial, we studied 37 patients (52 +/- 11 yrs) with low density lipoprotein cholesterol > or = 160 mg/dl (196 +/- 44 mg/dl) randomly assigned to either cerivastatin (0.4 mg/d) or placebo. Endothelium-dependent vasodilation of the forearm vasculature was measured by plethysmography and intra-arterial infusion of acetylcholine (ACh 12, 48 microg/min) and endothelium-independent vasodilation by intra-arterial infusion of nitroprusside (3.2, 12.8 microg/min).

RESULTS

Low density lipoprotein cholesterol decreased after two weeks of treatment (cerivastatin -33 +/- 4% vs. placebo + 2 +/- 4%, x +/- SEM, p < 0.001). Endothelium-dependent vasodilation improved after two weeks of therapy with cerivastatin compared with baseline (ACh 12 microg/min: + 22.3 +/- 5.2 vs. + 11.2 +/- 1.9 ml/min/100 ml, p < 0.01; ACh 48 microg/min: +31.2 +/- 6.3 vs. +19.1 +/- 3.1 ml/min/100 ml, p < 0.05). In contrast, changes in forearm blood flow to ACh were similar before and after therapy in the placebo group (ACh 12 microg/min: + 12.9 +/- 3.6 vs. + 9.0 +/- 1.9 ml/min/100 ml, NS; ACh 48 microg/min: +20.7 +/- 3.7 vs. 19.4 +/- 2.9 ml/min/100 ml, NS). Endothelium-dependent vasodilation improved in comparison with placebo (ACh 48 microg/min: +203 +/- 85% [cerivastatin] vs. -26 +/- 71% [placebo], p < 0.05). This improvement in endothelium-dependent vasodilation was no longer observed when the nitric oxide-synthase inhibitor N(G)-monomethyl-L-arginine was coinfused (ACh 48 microg/min + N(G)-monomethyl-L-arginine 4 micromol/min -48 +/- 85% [cerivastatin]).

CONCLUSIONS

Short-term lipid-lowering therapy with cerivastatin can improve endothelial function and NO bioavailability after two weeks in patients with hypercholesterolemia.

Preparation of site-differentiated mixed ligand and mixed ligand/mixed metal metallacrowns

Assembly reactions that can prepare reliably regioselective metallamacrocyclic complexes have been a target in the development of metallacrowns. To this end, a series of mixed ligand and mixed ligand/mixed metal metallacrowns have been synthesized in high yield and structurally characterized. Two distinct connectivities have been observed in these types of metallacrowns. The monomeric, vacant metallacrown with mixed ligand composition [12-MC(Ni(II)N(Hshi)2(pko)2-4)] (1a) shows the connectivity pattern [-O-Ni-O-N-Ni-N-]2 while the other Ni metallacrowns, [12-MC(Ni(II)N(shi)2(pko)2-4)] (2a) and the coupled [12-MC(Ni(II)N(shi))2(pko)2-4)][12-MC(Ni(II)N(shi))3(pko)-4)] (3a) fused metallacrowns as well as the mixed metal Mn-Ni metallacrown [12-MC(Ni(II)Mn(III)N(shi)2(pko)2-4)] (4a), follow the pattern [-Ni-O-N-]4. Also, three distinct arrangements of the chelate rings around the metal ions have been observed. The syntheses are completely general, allowing for the substitution of different ligands into the metallacrown core. Compounds 1 and 4 show the 6-5-6-5-6-5-6-5 arrangement, compounds 2 and 3(1) the 6-6-5-5-6-6-5-5, and the 3(2) component the 6-6-5-5-6-5-6-5. The obtained structures can be rationalized by balancing the charge at each metal site in the metallacrown. Variable temperature magnetic susceptibility measurements show that exchange interactions for all the compounds are weak and dominantly antiferromagnetic (e.g., 2a gives an exchange coupling of J = -1.2 cm(-1) with g = 2.2). In solution, the metallacrowns are shown to be stable both to decomposition and ligand exchange.

Phase II trial of a paclitaxel-carboplatin combination in recurrent squamous cell carcinoma of the head and neck

OBJECTIVE

Twenty-seven patients with recurrent squamous cell carcinoma of the head and neck were entered in a multicenter study to determine the efficacy of the paclitaxel-carboplatin association.

METHODS

Standard eligibility criteria applied, i.e. measurable disease, and chemotherapy given as induction treatment or concomitant chemoradiotherapy was allowed if completed more than 6 months prior to the study. Every 21 days, paclitaxel 175 mg/m(2) and carboplatin AUC 6 were administered. The patient group included 3 females and 24 males with a median age of 61 years (range 39-75 years).

RESULTS

All patients were assessable for toxicity and 24 for responses. Main grade 3-4 toxicities were: neutropenia (62.9%), febrile neutropenia (18.5%), anemia (11.1%), thrombocytopenia (14.8%), mucositis (7.4%) and vomiting (7.4%). Among the intent-to-treat population, 29.6% of patients had an objective response, with a median response duration of 4.2 months (range 1-5.7 months). Stable and progressive disease were observed in 11.1 and 48.1% of patients, respectively. The median overall survival was 7.2 months (range 0.5-10.9 months).

CONCLUSION

From these data, paclitaxel-carboplatin seems to have an activity in recurrent squamous cell carcinoma of the head and neck, but the high level of toxicity highlights the need to search for a safer chemotherapy combination.

[Man-nature-technology. Philosophical considerations of human-animal-relations]

Man's position in nature is equivocal. Man is part of nature and through evolution is linked to other living beings. Although an "Animal among Animals", nature has provided him with capabilities that separate him from all living beings in its realm. These comprise the ability for reflection and subsequent moral behavior, but also the gift (and necessity) for using technology to shape and subjugate his natural environment. Based upon this "Dual Nature of Man" the essay focuses on the web of interactions between Man, Nature and Technology. Modern ethics of animal protection argue in favor of extending the principle of equality ("To Each His Own") to include animals as well. However, the principle of equality is a purely formal, heuristic rule for assigning morally just determinations of value. It requires normative padding as far as its content is concerned. Consequently, the content of the principle of equality ought to be more closely determined in keeping with the ideal of humanity.

Protective effects of vitamins C and E on the number of micronuclei in lymphocytes in smokers and their role in ascorbate free radical formation in plasma

Cigarette smoke is widely believed to increase free radical concentrations causing subsequent oxidative processes that lead to DNA damage and hence, to several diseases including lung cancer and atherosclerosis. Vitamin C is a reducing agent that can terminate free-radical-driven oxidation by being converted to a resonance-stabilized free radical. To investigate whether short-term supplementation with the antioxidants vitamin C and E decreases free-radical-driven oxidation and thus decreases DNA damage in smokers, we determined the frequency of micronuclei in lymphocytes in 24 subjects and monitored the electron paramagnetic resonance signal of ascorbate free radical formation in plasma. Further parameters comprised sister-chromatid exchanges and thiobarbituric acid-reactive substances. Twelve smokers and twelve non-smokers took 1000 mg ascorbic acid daily for 7 days and then 1000 mg ascorbic acid and 335.5 mg RRR-alpha-tocopherol daily for the next 7 days. Baseline concentrations of both vitamins C and E were lower and baseline numbers of micronuclei were higher (p < 0.0001) in smokers than in non-smokers. After 7 days of vitamins C and E, DNA damage as monitored by the number of micronulei was decreased in both, smokers and non-smokers, but it was more decreased in smokers as indicated by fewer micronuclei in peripheral lymphocytes (p < 0.05). Concomitantly, the plasma concentrations of vitamin C (p < 0.001) as well as the ascorbate free radical (p < 0.05) were increased. The corresponding values in non-smokers, however, did not change. Our findings show that increased ascorbate free radical formation in plasma after short-term supplementation with vitamins C and E can decrease the number of micronuclei in blood lymphocytes and thus DNA damage in smokers.

G-protein beta(3) subunit gene (GNB3) 825T allele is associated with enhanced renal perfusion in early hypertension

The C825T polymorphism of the gene encoding the G-protein beta(3) subunit (GNB3) is associated with increased intracellular signal transduction and arterial hypertension. The aim of the study was to investigate the impact of this polymorphism on early adaptive processes of the left ventricle and renal hemodynamic changes in young normotensive to mildly hypertensive subjects. Ninety-five white male students with normal or mildly elevated blood pressure were genotyped for the GNB3 C825T polymorphism. In each participant, 24-hour ambulatory blood pressure, left ventricular structure and function (2D-guided M-mode echocardiography), renal plasma flow (para-aminohippurate clearance), glomerular filtration rate (inulin clearance), and 24-hour urinary sodium excretion were determined. The GNB3 825T allele was not associated with casual or ambulatory blood pressure, parameters of left ventricular structure or function, glomerular filtration, or 24-hour urinary sodium excretion. However, in T:-allele carriers (CT+TT), renal plasma flow was higher than in CC subjects (CT/TT: 659+/-96 versus CC: 614+/-91 mL/min, P:=0.019). ANOVA disclosed that renal plasma flow was independently influenced by both genotype and blood pressure, with hypertensives having a higher renal plasma flow than normotensive subjects. This was the fact irrespective of the criteria used for the definition of hypertension (World Health Organization or 24-hour ambulatory blood pressure criteria). The GNB3 825T variant is associated with increased renal perfusion in this study. Because early renal hemodynamic changes play a pivotal role in the pathogenesis of essential hypertension, our data suggest a relevance of increased G-protein activation in the pathogenesis of hypertension.

Differences between adolescents and young adults at presentation to an eating disorders program

OBJECTIVE

To describe differences between adolescents and adults in clinical presentation of eating disorders.

METHODS

Data from the charts of 622 female patients treated for an eating disorder in a division of adolescent medicine between 1980 and 1994 were coded and computerized. General categories included demographic and family factors, weight loss and weight changes, eating-related behaviors, diagnosis and severity, and treatment issues. Differences between the 438 patients who were aged 9-19 years (adolescents) and 184 patients who were aged 20-46 years (adults) were analyzed.

RESULTS

Adolescents were more likely than adults (p <.05) to have a diagnosis of "eating disorder not otherwise specified," lower global severity score, greater denial and less desire for help, weight loss > or = 3 lb/month, lower original and maximum weights, and history of fasting and elimination of junk food from their diets. Adults were more likely than adolescents (p <.05) to have >1 year of weight loss, greater total weight loss, history of binge eating and laxative use, history of diuretic and ipecac use, diagnosis of bulimia nervosa, and prior use of psychiatric medications. Adolescents and adults did not differ (p >.05) in parents' occupational level; height, weight, and percent ideal body weight at presentation; original percent ideal body weight; use of diet pills, elimination of meat and use of a low-fat diet; daily calorie intake; prior eating disorder hospitalizations; and hospitalization during the course of treatment.

CONCLUSIONS

The findings in this study document and confirm that there are important differences between adolescents and adults that must be taken into account in the evaluation and treatment of patients with eating disorders.

Primary lung sarcomas: long survivors obtained with iterative complete surgery

Primary lung sarcomas are uncommon histologic types of primary lung cancer and presents a wide spectrum of clinical behaviour. Nine patients treated at Antoine Lacassagne Cancer Center between 1982 and 1995 were studied. The median age was 63 years (range, 35-73 years) and the most common histologic types were malignant fibrous histiocytoma (four) and leiomyosarcoma (three). All of them underwent surgery, six patients had a complete surgery and three patients incomplete resections. The median overall survival for all patients was 36 months. In the subgroup of patients with initial complete resection, the median survival was significantly longer (47 months) than in the subgroup of patients with incomplete resection (6 months) (P<0.05, log-rank test). Moreover, two patients had a second complete resection for ipsilateral lung relapse and were long survivors (overall survival of 58 and 83 months, respectively). The ability to achieve a complete second surgery stress the possible benefit of an early detection of local recurrence. Because no specific symptom was linked with the local relapse, a systematic CT scan every 2 or 3 months could be required.

Emergency contraception: pediatricians' knowledge, attitudes, and opinions

Emergency contraception (EC) is the use of a method of contraception after unprotected intercourse to prevent unintended pregnancy. Although first described over 20 years ago, physician awareness of EC has been limited and many feel uncomfortable prescribing it.

OBJECTIVE

To assess the knowledge, attitudes, and opinions of practicing pediatricians regarding the use of EC in adolescents.

METHODS

An anonymous questionnaire was mailed to all 954 active members of New York Chapter 2, District II of the American Academy of Pediatrics. The questionnaire assessed basic knowledge, attitudes, and opinions regarding EC in adolescents. Data were analyzed by physician age, gender, year completed residency, and practice type.

RESULTS

Two hundred thirty-three practicing pediatricians (24.4%) completed the survey. Of the respondents, 23.7% had been asked to prescribe EC to an adolescent and 49% of these cases involved a rape victim. Only 16.7% of pediatricians routinely counsel adolescent patients about the availability of EC, with female pediatricians more likely to do so. Most respondents (72.9%) were unable to identify any of the Food and Drug Administration-approved methods of EC. Only 27.9% correctly identified the timing for its initiation and only 31.6% of respondents felt comfortable prescribing EC. Inexperience with use was cited as the primary reason for not prescribing EC by 70% of respondents. Twelve percent cited moral or religious reasons and 17% were concerned about teratogenic effects. There were no differences in comfort level based on age, gender, or practice type. Twenty-two percent of respondents believed that providing EC encourages adolescent risk-taking behavior and 52.4% would restrict the number of times they would dispense EC to an individual patient. A minority of respondents (17%) believed that adolescents should have EC available at home to use if necessary and only 19.6% believed that EC should be available without a prescription. The vast majority (87.5%) were interested in learning more about EC.

CONCLUSIONS

Despite the safety and efficacy of EC, the low rate of use is of concern. Pediatricians are being confronted with the decision to prescribe EC but do not feel comfortable prescribing it because of inadequate training in its use. Practicing pediatricians are aware of their lack of experience and are interested in improving their knowledge base.

Comparison between nasogastric tube feeding and percutaneous fluoroscopic gastrostomy in advanced head and neck cancer patients

Wasting is a major complication of advanced head and neck cancer and the aim of this study was to compare nasogastric tube feeding (NG) and percutaneous fluoroscopic gastrostomy (PFG) in these patients. The goal of these two methods of nutritional support was to improve or maintain the initial nutritional status during treatment. A total of 90 patients, all stage IV oropharynx or hypopharynx tumor, were reviewed from a prospective databank. All these patients were treated by concomitant chemotherapy and twice-daily continuous radiotherapy with no acceleration. Fifty patients were managed by PFG, and the rest by NG. Mechanical failure, duration of feeding, complications, nutritional evaluation and quality of life were analysed. Mechanical failure occurred in 32 of the 40 NG patients and in seven of the gastrostomy group. In the PFG group, 80% of patients conserved their nutritional support after the end of the radiotherapy, none patient in the NG group. In the PFG group, two presented a wound infection and six had aspiration pneumonia while in the NG group, 21 had aspiration pneumonia probably due to the NG tube (gastroesophageal reflux). The feeding methods were found to be equally effective at maintaining body weight and body mass index at time 1 (3 weeks) and at time 2 (6 weeks). Advantages were associated with PFG cosmesis, mobility and quality of life. PFG is a safe and effective method of providing enteral nutrition during treatment to patients with advanced head and neck cancer and offers important advantages over NG.

Inhibition of the I(h) current in isolated peripheral nerve: a novel mode of peripheral antinociception?

Although the alpha2-adrenergic agonist clonidine has been shown to promote peripheral antinociception, its mechanism of action has not yet been clearly elucidated. By the use of the sucrose-gap method, we have shown that in C fibers of the rabbit vagus nerve, clonidine at micromolar concentrations enhances activity-dependent hyperpolarizations generated by the Na+-K+ pump during and after repetitive stimulation. Similar results were obtained with 10 microM of ZD 7288, a specific blocker of the hyperpolarization-activated cation current (I(h)) and with 2 mM of Ba2+ that blocks the inwardly rectifying potassium current (I(KIR)). Furthermore, clonidine had no added effect on the ZD 7288-induced response, whereas it produced a marked enhancement of Ba2+induced response. From these results, it can be concluded that clonidine enhances activity-dependent hyperpolarization by inhibiting the current I(h). We propose that clonidine, by increasing the threshold for initiating the action potential, induces a slowing or block of conduction and that this mechanism is the origin of the clonidine-induced antinociception. Finally, this study suggests a novel role for inwardly rectifying hyperpolarization-activated conductances in peripherally mediated antinociception.

Morphometric assessment of testicular changes in drug-related fatalities

Testicular sections of 50 deceased drug addicts were examined by light microscopy using morphometric methods and determining the extent of spermatogenesis by application of the Johnsen score count. Twenty cases of violent death served as reference sample. The study was aimed at obtaining data about the degree of germinal gland damage following the duration of the individual drug career, which was correlated to the histologic findings. Progressively reduced maturation of germinal cells, decrease of tubular diameter and height of sperm-producing epithelium were found the longer the individual case history has been. The results clearly indicated a substantial impairment of male fertility in the course of a drug career, but etiology seems to be multifactorial, since most of the deceased were polytoxicomanic and more than 40% were under the influence of alcohol at the time of death. Testicular damage is obviously a sequel of long-lasting abuse and a very complex process, presumably progressing with the duration of the adverse habit.

Incomplete lupus erythematosus: results of a multicentre study under the supervision of the EULAR Standing Committee on International Clinical Studies Including Therapeutic Trials (ESCISIT)

OBJECTIVE

Patients characterized with antinuclear antibodies (ANA) and disease symptoms related to one organ system can be described as having incomplete systemic lupus erythematosus (SLE). The aim of this multicentre study was to describe the outcome of these so-called incomplete SLE patients. Two aspects of the outcome were studied: (i) the disease course, defined by the presence or absence of clinical symptoms; and (ii) the number of patients that eventually developed full SLE.

METHODS

Outcome parameters were the ACR criteria, the SLE disease Activity Index (SLEDAI), the European Consensus Lupus Activity Measure (ECLAM) and the requirement for treatment. In 10 European rheumatology centres, patients who had been evaluated in the last 3 months of 1994 and had been diagnosed as having incomplete SLE on clinical grounds for at least 1 yr were included in the study. All 122 patients who were included in the study were evaluated annually during 3 yr of follow-up.

RESULTS

Our results are confined to a patient cohort defined by disease duration of at least 1 yr, being under clinical care at the different centres in Europe. These patients showed disease activity that was related mostly to symptoms of the skin and the musculoskeletal system, and leucocytopenia. During the follow-up, low doses of prednisolone were still being prescribed in 43% of the patients. On recruitment to the study, 22 of the 122 incomplete SLE patients already fulfilled the ACR criteria for the diagnosis of SLE. In the 3 yr of follow-up only three patients developed SLE.

CONCLUSIONS

A high proportion of patients in our cohort defined on clinical grounds as having incomplete SLE eventually showed disease activity defined by the SLEDAI as well as ECLAM. However, only three cases developed to SLE during the follow-up. This suggests that incomplete SLE forms a subgroup of SLE that has a good prognosis.

A totally synthetic polyoxime malaria vaccine containing Plasmodium falciparum B cell and universal T cell epitopes elicits immune responses in volunteers of diverse HLA types

This open-labeled phase I study provides the first demonstration of the immunogenicity of a precisely defined synthetic polyoxime malaria vaccine in volunteers of diverse HLA types. The polyoxime, designated (T1BT(*))(4)-P3C, was constructed by chemoselective ligation, via oxime bonds, of a tetrabranched core with a peptide module containing B cell epitopes and a universal T cell epitope of the Plasmodium falciparum circumsporozoite protein. The triepitope polyoxime malaria vaccine was immunogenic in the absence of any exogenous adjuvant, using instead a core modified with the lipopeptide P3C as an endogenous adjuvant. This totally synthetic vaccine formulation can be characterized by mass spectroscopy, thus enabling the reproducible production of precisely defined vaccines for human use. The majority of the polyoxime-immunized volunteers (7/10) developed high levels of anti-repeat Abs that reacted with the native circumsporozoite on P. falciparum sporozoites. In addition, these seven volunteers all developed T cells specific for the universal epitope, termed T(*), which was originally defined using CD4(+) T cells from protected volunteers immunized with irradiated P. falciparum sporozoites. The excellent correlation of T(*)-specific cellular responses with high anti-repeat Ab titers suggests that the T(*) epitope functioned as a universal Th cell epitope, as predicted by previous peptide/HLA binding assays and by immunogenicity studies in mice of diverse H-2 haplotypes. The current phase I trial suggests that polyoximes may prove useful for the development of highly immunogenic, multicomponent synthetic vaccines for malaria, as well as for other pathogens.

Lupus-like syndrome with submassive hepatic necrosis associated with hepatitis A

Hepatitis A is a common self-limited liver disease. However, 15% of patients may have some complications. Autoimmune hepatitis that is triggered by viral hepatitis has been reported. We hereby describe an unrecognized association of hepatitis A with a full blown lupus-like syndrome manifested by the appearance of arthralgia, exudative pleural effusion with the presence of lupus erythematosus cells and autoantibodies. All these findings disappeared after a short course of steroid treatment. The case is presented and the literature is reviewed.

[Public health in the central and eastern European countries]

During the last two decades, the countries of Central and Eastern Europe have been transforming their health systems and built an intermediate model between market and socialised economies. At the same time, they have been trying to establish a system of observed in public health between the countries of the European Union and those of Central and Eastern Europe widened in the last decade. In view of accessing the European Union, this article develops the different points in a context where public health represents a topic of extreme importance for the European Commission.