Antipicornavirus activity of SCH 47802 and analogs: in vitro and in vivo studies

SCH 47802 and its derivatives are potent inhibitors of enteroviruses in vitro. The IC50 for SCH 47802 ranges from 0.03 to 10 micrograms/ml when tested against a spectrum of enteroviruses in plaque reduction assays. The compounds have in vitro therapeutic indices of at least 81 based on viral cytopathic effect (CPE) assays. The in vitro activity of SCH 47802 translates into in vivo activity in the murine model of poliovirus encephalitis. In an oral dosing regimen, SCH 47802 protects mice from mortality at 60 mg/kg per day. Consistent with the in vivo efficacy, pharmacokinetic analyses after oral dosing with SCH 47802 demonstrate serum levels of the compound above the in vitro IC50 for poliovirus for at least 4 h. SCH 47802 and its active analogs stabilize poliovirus to thermal inactivation indicating that the compounds bind to the virus capsid. Mechanistic studies with poliovirus indicate that SCH 47802 acts early in viral infection. This series of molecules represents potential candidates for the treatment of human enterovirus infections.

Pharmacokinetic Study of Triflusal in Elderly Subjects After Single and Repeated Oral Administration

In this study the single-dose and steady-state pharmacokinetics of unchanged triflusal and its metabolite 2-hydroxy-4-trifluoromethylbenzoic acid (HTB) were studied in 12 elderly subjects treated with a single oral administration of 300 mg triflusal and repeated oral administrations of 300 mg triflusal b.i.d. for 13 days. After a single administration, unchanged triflusal is promptly absorbed (t(max) 0.75 h, C(max) 3.83 &mgr;g/mL) and rapidly depleted from the systemic circulation. Its concentration was measurable only up to 1 to 4 h after administration. The apparent terminal half-life was 0.85 h. HTB proves to be quickly generated from triflusal (t(max) 2.00 h, C(max) 39.88 &mgr;g/mL) and slowly eliminated from the body (t = 54.6 h). With the dose regimen proposed, unchanged triflusal does not accumulate in the body. Conversely, HTB plasma concentration builds up progressively toward steady-state levels of approximately 102 &mgr;g/mL after 4 to 5 d of treatment. No substantial change in peak time, elimination rate constant and half-life evaluated after single-dose treatment was observed on multiple-dose regimen for unchanged triflusal and its metabolite HTB. Therefore, our findings do not indicate a time-dependent pharmacokinetics for triflusal. There were no changes in blood pressure, heart rate or laboratory safety date, i.e., biochemical or hematological profiles.

Enzymatic characterization of hepatitis C virus NS3/4A complexes expressed in mammalian cells by using the herpes simplex virus amplicon system

The hepatitis C virus (HCV) NS3 protein possesses three enzymatic activities: an N-terminal serine protease activity, a C-terminal RNA-stimulated NTPase activity, and an RNA helicase activity. To characterize them, the full-length NS3(631)/4A and three C-terminal truncated proteases (NS3(201)/4A, NS3(181)/4A, and NS3(155)/4A were expressed in mammalian cells with HSV amplicon-defective viruses. Our results revealed that all of the NS3/4A proteins produced in mammalian cells (except NS3(155)/4A) are active in processing both cis and trans cleavage sites. Temperature optimization studies revealed that the protease is more active at temperatures ranging from 4 to 25 degrees C and is completely inactive at 42 degrees C. The RNA-stimulated ATPase activity was characterized with a partially purified NS3(631)/4A fraction and has a higher optimal temperature at 37 to 42 degrees C. The effects of detergents on both NS3 protease and RNA-stimulated ATPase were similar. Nonionic detergents such as Triton X-100, Nonidet P-40 and Tween 20 did not affect the activities, while anionic detergents such as sodium dodecyl sulfate and deoxycholic acid were inhibitory. Zwitterionic detergent such as 3-[(3-cholamidopropyl)- dimethyl-ammoniol-1-propanesulfonate (CHAPS) inhibited protease activity at a concentration of 0.5% (8 mM), which had no effect on ATPase activity. Finally, RNA-unwinding activity was demonstrated in the NS3(631)/4A fraction but not in the similarly purified NS3(181)/4A and NS3(201)/4A fractions. NS(363)/4A unwinds RNA duplexes with 3' but not 5' single-stranded overhangs, suggesting that the NS3 RNA helicase functions in a 3'-to-5' direction.

Needle aspiration techniques in preoperative selection of patients with thyroid nodules: a long-term study

PURPOSE

Long-term evaluation of the combination of two needle aspiration techniques (NAT) (fine-needle aspiration [FNA] and aspiration needle biopsy [ANB]) in performing an efficient preoperative selection of palpable thyroid nodules.

PATIENTS AND METHODS

Eight years of extensive use of surgery for the detection of thyroid cancer was compared with 12 years of preoperative selection of by NAT.

RESULTS

A total of 1,140 operations were performed from 1972 to 1979, and 35 malignant nodules were discovered (3.1%). Five thousand four hundred three patients were examined by NAT from 1980 to 1992; 483 (9%) underwent surgery and 158 malignant nodules were excised. The number of malignant nodules identified by NAT was 166 (eight were not excised) (3.1% of the total population examined). The principal clinical and pathologic features were similar in both groups. ANB yielded a definite benign diagnosis in 88 patients with inadequate FNA findings, it correctly identified four malignant nodules diagnosed as benign by FNA, it showed a macrofollicular component in 115 nodules diagnosed by FNA as microfollicular nodules, and it significantly changed the predictive value of 79 suspicions FNA diagnoses.

CONCLUSION

Introduction of NAT reduced the number of operations for palpable thyroid nodules from 143 to 40 per year and increased from four to 13 the number of malignant nodules excised without any change in the overall incidence of malignant nodules. The combination of ANB to FNA significantly contributed to the high and efficient preoperative patient selection, principally by reducing the number of indeterminate or suspicious, as well as false-negative, preoperative FNA diagnoses.

Immunoendocrine aspects of anorexia nervosa

The T-lymphocyte proliferative response to phytohemoagglutinin (PHA) stimulation was the same in 11 anorexic women, 6 restricted (AN-R) and 5 bulimic (AN-B), and in 11 sex- and age-matched controls, in basal conditions and after acute administration of corticotropin-releasing hormone (CRH). Basal plasma levels of ACTH and cortisol were higher in patients than in controls, while beta-endorphin (beta-EP), growth hormone (GH) and prolactin (PRL) concentrations did not differ in the two groups. ACTH and beta-EP responses to CRH stimulation were blunted in patients, while those of cortisol did not differ in the two groups. ACTH, beta-EP and cortisol responses to the dexamethasone suppression test were impaired in 55% of the patients. Baseline T-lymphocyte concentrations of cholecystokinin-8 (CCK-8) and beta-EP were measured in another group of 56 anorexics, 33 restricted and 23 bulimic, and in 24 controls. CCK-8 values were significantly lower and beta-EP values significantly higher in patients than in controls.

[High-dose chemotherapy and peripheral hemtopoietic cells (PBPC) in solid tumors]

High-dose chemotherapy is a policy which is increasing in the field of solid tumors both in Europe and in North America. Hundreds of patients undergo ABMT or PBPCT in Europe every year especially for breast carcinoma. Waiting for the results of several ongoing trials, high-dose chemotherapy has shown to be of extreme interest in the adjuvant setting of patients with high risk breast cancer in phase II trials. The best results had been reported by Peters and Gianni; with a minimum follow-up of 5 years 65 and 56% of their patients with ten or more axillary lymph nodes are alive disease free. These results are better than any others with standard doses. The only one published trial (from South Africa) on advanced disease clearly favours high-doses of cyclophosphamide, mitoxantrone and etoposide versus standard doses of cyclophosphamide, mitoxantrone and vincristine in terms of overall survival and time to relapse. The use of PBPC replacing ABMT has allowed an easier tolerability of the procedure and a reduction of the costs. There is a clear reduction of the toxic death rate to 1% in 1995 for breast cancer patients compared with 20% of fifteen years ago. Germ cell tumors in responding relapse after salvage chemotherapy seem to be ideal candidates for ABMT/PBPC programs with an expected 40% disease free survival. The clinical impact of the PBPC contamination by tumor cells is still nowadays a matter of debate at least for breast carcinoma and neuroblastoma. This review will focus on the present situation of high-dose chemotherapy for solid tumors with some insights to new technologies and their applications.

[Complete regression of cardiac non-Hodgkin's lymphoma after 23 months with chemotherapy]

The authors report the case of a non-Hodgkin malignant lymphoma (NHL) of the heart presenting with syncope. The diagnosis of a cardiac tumours was made by echocardiography. Myocardial biopsy enabled diagnosis of a highly malignant NHL in a patient with a history of low grade NHL. Chemotherapy with CNOP (Cyclophosphamide, Novantrone, Oncovin, Prednisone) induced total regression of the tumour. The patient is in total remission 23 months later. The authors emphasise the value of echocardiography in the diagnosis and follow-up of this pathology. The case is also noteworthy because of the unusual transformation of a low grade to a high grade cardiac NHL.

A functional Spo0A is required for maximal aprE expression in Bacillus subtilis

The initiation of sporulation in Bacillus subtilis is under control of the transcriptional factor Spo0A. Most Spo0A mutants fail to initiate the sporulation process and all the sporulation initiated processes such as the synthesis of subtilisin. However, the product of spo0A9V, one of the several spo0A mutants characterized, distinguishes itself in the fact that, while it appears to effectively repress abrB, it fails to activate the spoIIA operon. The aim of this study was to examine the effect of the spo0A9V mutation on aprE expression and we found that in different genetic backgrounds, the spo0A9V mutation has a negative effect on aprE::lacZ expression.

Aspiration needle biopsy refines preoperative diagnosis of thyroid nodules defined at fine needle aspiration as microfollicular nodule

The aim of this paper was to verify the hypothesis that large needle biopsy performed preoperatively can refine preoperative fine needle aspiration (FNA) cytological diagnoses of microfollicular nodules. Since 1980 we have been using FNA and aspiration needle biopsy (ANB) (18 or 16 gauge needles) to select for surgery all euthyroid patients with palpable thyroid nodules referred to our department. From 1980 to 1994, 6,124 patients (12% male, 88% female) with thyroid nodules (71% single, 29% multiple) were examined by FNA; 29% of these patients were also examined preoperatively by ANB histology. Of all the nodule patients examined, 371 received a preoperative FNA diagnosis of microfollicular nodule. Two hundred and fifty-four of these nodules (68%) were also examined preoperatively by ANB. Unsatisfactory ANB specimens constituted 17% of cases; pure microfollicular structure was confirmed by ANB in 36% of the nodules; ANB showed the remaining 47% to contain a macrofollicular component, thus suggesting a benign hyperplastic lesion. Twelve nodules which were found to be microfollicular at FNA cytology and micro-macrofollicular at ANB were excised and were subsequently determined as benign at definitive postoperative histology. These data indicate the utility of ANB in refining the preoperative FNA diagnosis of microfollicular nodule and in preoperatively identifying benign hyperplastic mixed micro-macrofollicular lesions which can be followed by observation.

Long-term GnRH-agonist administration revealed a GnRH-independent mechanism stimulating FSH discharge in humans

The present study evaluated the FSH and LH episodic discharge in different physiopathological conditions undergoing chronic GnRH-agonist administration. Four girls with true precocious puberty and five postmenopausal women were administered GnRH-agonist (3.73 leuprolide acetate every 4 weeks; Takeda Italia, Rome, Italy) for at least 4 months. Plasma LH and FSH secretory profiles were assessed before and under GnRH-agonist administration (after 21 and 120 days). Pulsatility studies were conducted for 4 h in the girls and for 6 h in postmenopausal women, with blood sampling intervals of 10 min. Pubertal and postmenopausal patients showed the distinct episodic co-secretion of LH and FSH before GnRH-agonist administration; this co-secretion disappeared in both groups after 21 and 120 days of treatment. Moreover, while LH concentrations decreased to almost undetectable levels and LH episodic release disappeared, FSH plasma levels were only partially reduced and FSH episodic secretion was detectable in both groups. In conclusion, this study demonstrated that long-term GnRH-agonist administration blocked LH but not FSH episodic release. These data enforce the hypothesis that FSH episodic discharge might be dependent not only on hypothalamic GnRH, but also on a GnRH-independent stimulatory pathway.

[Duration of antivitamin K therapy in venous thromboembolic disease]

The necessity for anticoagulant treatment after pulmonary embolism or deep vein thrombosis has been demonstrated. The modalities of this treatment have been established, especially the value of initial heparin relayed by oral antivitamin K therapy with a target INR value between 2 and 3. The last question remaining in this protocol is that of the duration of anticoagulant treatment. The choice of duration of anticoagulation should take into consideration two potential complications: haemorrhage due to over-anticoagulation and excessive duration of therapy, and recurrent thromboembolism which could result from an inadequate duration of therapy. Several trials have addressed this question and have led to a consensus of opinion: therefore, secondary venous thrombo-embolic disease, occurring under known, special circumstances, the cause of which has been treated, should be given 4 to 6 weeks anticoagulant therapy. In the other cases, so-called idiopathic venous thromboembolism (the proportion of which is on the increase), recent studies are inadequate to reach a consensus. These "idiopathic" forms are characterised by a higher incidence of recurrent thromboembolism of "secondary" cancer and coagulation abnormalities. The search for the optimal duration of anticoagulant therapy in these forms requires prospective trials taking their features into account and should lead to further therapeutic options. The evaluation of longer treatment protocols with less intensive degrees of anticoagulation and of alternatives to oral vitamin K antagonists is justified.

[Epidemiology of pulmonary embolism]

There are few conditions in medicine as difficult to diagnose as pulmonary embolism. This is certainly not due to the rarity of the disease which is probably as common as myocardial infarction in France. The circumstances surrounding pulmonary embolism and the risk factors of deep venous thrombosis have been well identified. The risk of thromboembolic venous disease has been assessed for each type of surgery. The methods of treatment and prevention have progressed over a number of years. However, in practice, these advances have not "transformed" the frequency of the disease or reduced its mortality. Further progress could come from improved identification of patients at risk, especially by biological tests and new abnormalities of blood coagulation.

IDDM in the province of Pavia, Italy, from a population-based registry.A descriptive study

OBJECTIVE

To report the incidence of insulin-dependent diabetes mellitus (IDDM) in the Province of Pavia, Italy, in the 0- to 29-year-old age-group between 1988 and 1992. Urban versus rural residence, socioeconomic level, and family size of IDDM cases were also investigated.

RESEARCH DESIGN AND METHODS

A prospective register was established in 1988 to collect all newly diagnosed IDDM patients with onset before 30 years of age. The primary data source was based on notification of new cases by hospitals, out-patient clinics, family doctors, and pediatricians. The secondary and independent data source consisted of the registries of prescriptions for insulin syringes in the health districts of the province.

RESULTS

In 5 years (1988-1992), 66 cases of IDDM in the 0- to 29-year-old age-group were identified. The completeness of ascertainment was 100% for the combined sources. Age-adjusted (world-standardized) incidence rates per 100,000 (95% confidence interval) were 9.52 (6.42-13.61), 6.72 (4.68-9.34), and 8.27 (6.42-10.58), respectively, for the age-groups 0-14, 15-29, and 0-29. The rates were higher for residents in urban areas. The number of children in the families of IDDM patients was significantly higher than in the reference population.

CONCLUSIONS

Our data indicate the concordance of IDDM incidence rates with the North-Italian rates and a possible association of the disease with environmental factors. These factors might enhance the susceptibility to IDDM in genetically predisposed individuals.

[Piperacillin in prevention and therapy in gynecological surgery]

The authors have studied the use of sodic piperacillin in surgical gynecological prophylaxis. The drug, used in the intravenous tract, has proved efficacious for broad spectrum of antibacterial action versus gram+, gram-, and anaerobic and aerobic. It has shown an excellent tolerability by reducing hospital surgical infections (11% of cases) and sepsis (9.2% of cases) with social, economic and professional advantages.

Continuous wave Nd:YAG laser photocoagulation in proliferative diabetic retinopathy

AIMS

The therapeutic efficacy of the continuous wave (CW) Nd:YAG laser (working in the free running mode) was investigated in proliferative diabetic retinopathy (PDR) comparing it with a conventional laser source such as the krypton laser.

METHODS

Twenty four eyes of 12 patients affected with bilateral PDR were included and divided in two groups. The right eyes were treated with a red krypton laser and the left eyes with a CW Nd:YAG laser.

RESULTS

Three months after krypton photocoagulation 10 eyes showed a reduction or a complete regression of PDR and two eyes were unchanged. In the CW Nd:YAG laser group no eyes showed any regression of new vessels, in seven eyes the angiographic features were unchanged, and in five eyes they worsened. All the eyes of the second group underwent retreatment with the krypton laser after 3 or 6 months. After a mean follow up of 13 months all eyes in the krypton group showed a reduction or complete regression of PDR; in the retreated group 10 eyes improved and two were unchanged.

CONCLUSIONS

The statistical analysis showed a highly significant difference (p = 0.001) between krypton and CW Nd:YAG laser which indicated the lack of efficacy of the latter in the treatment of PDR. In the krypton laser group no significant difference (p = 0.05) after the retreatment was found confirming the efficacy of this treatment.

Neuroendocrine correlates of the aging brain in humans

Physiological brain aging is characterized by important biochemical and structural changes and by the unbalance among the different neurotransmitters and neuromodulators. The study of the circadian organization of neuroendocrine functions may be considered a clinically reliable tool to investigate the changes of the CNS and particularly of the limbic-hypothalamic system occurring in aged people. The circadian rhythms of plasma melatonin, ACTH and cortisol and of oral temperature were studied in 16 clinically healthy women aged 66-90 years and in 14 young controls aged 20-30. In addition, the effect of dexamethasone on the plasma cortisol circadian rhythm and the cortisol response to Synacthen pulse intravenous injection were evaluated. All subjects were studied as inpatients, with the same synchronization to the hospital life schedule. When compared with young controls, elderly subjects exhibited a reduction of the mean level and of the amplitude of the circadian rhythm of oral temperature, an increase of the mean level of ACTH and cortisol rhythms and a selective impairment of melatonin nocturnal secretion. Furthermore, elderly subjects showed a reduced sensitivity to the dexamethasone suppression test, by comparison to young controls. These changes were age-related and they may depend either on CNS modification or on alterations of the hormonal metabolic clearance.

[Refractory sinus tachycardia: late complication of radiotherapy]

The authors describe a case of sinus tachycardia, an unusual cardiac complication of mediastinal radiotherapy; occurring in two patients by the first days of treatment and persisting for several years. No other cause for this tachycardia could be detected in either case. Electrophysiological investigation of one of the two patients was normal. Despite the risk of a high-degree conduction disorder, "symptomatic" beta-blocker treatment was prescribed, but only induced a limited effect.

Short-latency median nerve somatosensory evoked potentials in three cases of parkinsonism and dopa responsive dystonia

We studied somatosensory evoked potentials after median nerve stimulation in a sporadic case of dopa responsive dystonia and in two brothers with different combinations of dystonia and parkinsonism. The latencies of all potentials were normal. The amplitude of the P20-N30 frontal complex showed a significant reduction in all cases. Our results suggest a common neurophysiopathological pattern underlying these two conditions.

[Which tests should be performed after phlebitis and/or pulmonary embolism?]

The lack of knowledge of the origin of venous thrombosis (VT) causes frustration and distress to the clinician. Some results published in the literature suggest a lot of potential aetiologies. Anyhow, we are far from getting a proof that a systematic and exhaustive search for a potential cause, for instance impairment of blood coagulation or infraclinical cancer, could be of benefit for the patient and could present a good cost/efficacy ratio. Consensus recommendations limit the extent of blood coagulation studies only to some precise clinical situations. New biological data evidencing a resistance to activated C protein in 20 to 50 per cent of VT cases, will likely bring new rules. As far as infraclinical cancers are concerned and whether their relationship to idiopathic VT is well-established, it is still doubtful that such systematic heavy and expensive checking up could be of any benefit.

Diode laser photocoagulation of choroidal hemangioma

BACKGROUND

The argon laser photocoagulation has recently become the treatment of choice in choroidal hemangioma. We evaluated the efficacy of the near infrared wavelength diode laser in the treatment of such tumours. This wavelength is not highly absorbed by the retinal pigment epithelium and penetrates deep into the choroid.

METHODS

Two cases of choroidal haemangioma with a serous detachment of the neural retina were diagnosed with ophthalmoscopy, fluorescein and indocyanine green angiography, A-scan and B-scan ultrasonography and treated with a surface photocoagulation with a diode laser. The efficacy of photocoagulation was evaluated three, six, twelve and fifteen months after laser treatment.

RESULTS

The resorption of the subretinal fluid and a reduction in thickness of the tumour followed laser photocoagulation.

CONCLUSIONS

Diode lasers might be effective in the treatment of choroidal haemangioma.

[Pulmonary hypertension caused by talcoma in a couple of drug addicts]

The authors report a case of severe pulmonary hypertension (PHT) in a couple of HIV seropositive heroin addicts. The parallel clinical course in these two patients with only mild immunodeficiency and the fact that they both had the same supplier were in favour of PHT secondary to talcoma. In the light of these cases, one wonders whether, as suggested by certain epidemiological studies currently underway, drug addiction should be considered to be a cause of PHT in its own right. According to the authors, this approach would underestimate the incidence of this disease in this particular population and would therefore bias the epidemiological data.