Synthesis and biological evaluation of new analogues of the active fungal metabolites N-(2-methyl-3-oxodecanoyl)-2-pyrroline and N-(2-methyl-3-oxodec-8-enoyl)-2-pyrroline

To evaluate the effect of simplifying the beta-ketoamide system present in active isolated metabolites from Penicillium brevicompactum (2 and 3) on the activity, new analogues with a monocarbonylic amide functionality have been obtained. In this way, the insecticidal and fungicidal activities have been improved in relation to the natural products taken as lead molecules. Thus, two of the synthetic analogues (5a and 5b) showed very important insecticidal activities against third-instar nymphs of Oncopeltus fasciatus Dallas, with acute LD(50) values of 3.0 and 1.5 microg/cm(2), respectively. Moreover, some analogues showed good levels of fungicidal activity against a wide range of commercially important and taxonomically diverse fungi; remarkably, compound 7c has proved to be highly active against Colletotrichum gloesporoides and Colletotrichum coccodes, with ED(50) values of 2.04 and 11.7 microg/mL, respectively.

Anticardiolipin antibodies in acute poststreptococcal glomerulonephritis and streptococcal impetigo

Anticardiolipin (aCL) antibodies have been described in diverse clinical situations, linked to the risk of thrombosis in different vascular locations. They have been rarely studied in renal diseases, and occasionally they have been associated with glomerular thrombosis. We analyzed the incidence of aCL (isotypes IgG, IgA, and IgM) in samples, taken during the acute phase of the disease, from 27 well-documented patients having acute poststreptococcal glomerulonephritis. Twelve cases were positive on IgG testing, 1 case on IgA testing only, and no one was positive on IgM testing. A serological follow-up was performed with a second sample taken about 7 months later, for the patients initially positive on IgG testing showing persistence in 9. Clinical variables during the acute phase and after a follow-up period of 25 (range 6-89) months were analyzed for possible associations with the presence of these antibodies, but non was significantly related. Renal histopathological investigation did not reveal particular findings in the aCL-positive patients, and glomerular thrombosis was not found in any case. In addition, serum samples from 12 streptococcal impetigo patients without renal involvement were analyzed, showing similar incidence (4 positive on IgG testing, 1 of them positive on IgM testing as well, and no one positive on IgA testing) and titers of aCL antibodies. We conclude that the presence of aCL antibodies in acute poststreptococcal glomerulonephritis may be a marginal immunological phenomenon unrelated to the glomerular disease, triggered by the streptococcal infection.

Antimicrobial and antioxidant compounds in the nonvolatile fraction of expressed orange essential oil

Three permethoxylated flavones, dehydroabietic acid and linoleil monoglyceride were isolated from the nonvolatile residue of orange essential oil. All of them exhibited antifungal activity against phytopathogenic species and food contaminants. The isolated hexa- and heptamethoxy flavones exhibited important fungicidal activity against Geotrichum candidum, which is not inhibited by the commercial broadspectrum fungicide Benomyl (methyl-1-[butylcarbamoyl]-2-benzimidazolecarbamate); in addition, these compounds also exhibited effective antioxidant activities, similar to that shown by tert-butyl-4-hydroxyanisol, one of the most commonly used synthetic antioxidants; alpha-tocopherol, the most widely used natural antioxidant, was also isolated.

Insecticidal, anti-juvenile hormone, and fungicidal activities of organic extracts from different Penicillium species and their isolated active components

Organic extracts from mycelium and culture broth of 21 Penicillium isolates have been tested for insecticidal, insect anti-juvenile hormone (anti-JH), and antifungal activities. Culture broth extracts were the most active, mainly against insects; nearly 25% of them have shown high entomotoxicity (100% mortality at 100 microg/cm(2)). A strong in vivo anti-JH activity against Oncopeltus fasciatus Dallas was detected in the culture broth extracts from P. brevicompactum P79 and P88 isolates. The two new natural products isolated from P79, N-(2-methyl-3-oxodec-8-enoyl)-2-pyrroline (1) and 2-hept-5-enyl-3-methyl-4-oxo-6,7,8,8a-tetrahydro-4H-pyrrolo[2,1-b]-1, 3-oxazine (2), possessed anti-JH and insecticidal activity, respectively, against O. fasciatus. Synthesized natural compound 1 has shown an ED(50) of 0.7 microg/nymph when assayed on newly molted fourth-instar nymphs of O. fasciatus. Promising biological activities have also been detected in the synthetic precursors.

[Diabetic neuropathy: thermal sensation and metabolic control in non-insulin-dependent diabetics]

BACKGROUND

The early detection of peripheral neuropathy in diabetics is important since it is the main risk factor for lower limb trophic lesions in diabetics.

AIM

To assess the relationship between feet thermal sensation threshold and metabolic control in ambulatory non-insulin-dependent diabetics.

PATIENTS AND METHODS

A random sample of 34 non-insulin-dependent diabetics followed for more than five years in a special clinic, out of 368 patients, was selected. Warmth sensation thresholds were measured in the dorsum of both feet using a MSTP-III thermostimulator. The average value of all glycosylated hemoglobins obtained during the 9.7 +/- 5.3 years of follow up for each patient was calculated. A multiple stepwise regression analysis was performed between thermal sensation as the dependent variable and glycosylated hemoglobin, fasting blood glucose, age and diabetes duration.

RESULTS

The regression model disclosed glycosylated hemoglobin as the only independent predictor of warmth sensation threshold (partial r = 0.385; p = 0.043). Fifteen diabetic patients with good metabolic control, defined as those with a mean glycosylated hemoglobin of less than 9.5%, had a warmth sensation threshold of 35.6 +/- 3.7 degrees C, whereas 19 diabetics with a had control (glycosylated hemoglobin > or = 9.5%) had a threshold of 39 +/- 3.8 degrees C (p = 0.017).

CONCLUSIONS

In this group of diabetics, there is a relationship between the severity of distal polyneuropathy and the metabolic control, assessed with glycosylated hemoglobin levels.

Incidence and studies on antigenic specificities of antineutrophil-cytoplasmic autoantibodies (ANCA) in poststreptococcal glomerulonephritis

Sera from 210 patients with Acute Poststreptococcal Glomerulonephritis (APSGN) and 14 patients with streptococcal impetigo without glomerular disease were tested for the presence of IgG-ANCA using an indirect immunofluorescence assay (IIF) on ethanol fixed normal human neutrophils. In the group of nephritic patients, ANCA were detected by IIF in 9% (18 out of 210 cases) in an atypical diffuse cytoplasmic pattern (a-ANCA) in 14 cases and in a (p-ANCA) perinuclear staining in the remaining 4 cases. Longitudinal studies performed on six IIF positive patients, showed persistence of the phenomenon for up to six months, without relationship with activity of disease. No patient with streptococcal impetigo showed positivity on the IIF assay. Positive sera were analyzed on ELISA plates for their IgG reactivity against specific purified ANCA antigens: Proteinase-3 (PR3), Myeloperoxidase (MPO). Cathepsin-G and Bactericidal/Permeability Increasing Protein (BPI). Anti-MPO antibodies were present in 4 cases (3 a-ANCA and 1 p-ANCA). No reactivity was identified against PR-3, BPI and Catepsin-G in any of the samples. The presence of ANCA was significantly associated with a more severe glomerular disease as assessed by the serum creatinine and the crescents formation. Further studies are required to identify other antigenic specificities of these autoantibodies. Their absence in the streptococcal impetigo control group might suggest that their presence in APSGN could play some pathogenic role in kidney disease.

Suprahepatic vein oxygen tension in alcoholics with severe and mild liver damage

We measured suprahepatic vein and arterial partial oxygen pressure in 35 alcoholics with severe (N = 7) or mild (N = 28) histological liver damage and without evidence of clinical liver failure. The suprahepatic vein was punctured with a fine needle, using a percutaneous approach. Suprahepatic vein partial oxygen pressure was lower and arterial-suprahepatic gradient higher in alcoholics with severe liver damage compared to those with mild damage (35.1 +/- 1.7 vs 44.1 +/- 2.1 and 58.9 +/- 3.7 vs 45.9 +/- 2.4 mm Hg, respectively; P < 0.001). Suprahepatic puncture was well tolerated and devoid of complications. It is concluded that alcoholics with severe liver damage have lower oxygen tensions in the suprahepatic vein, a phenomenon that supports the hypoxic theory of alcoholic liver disease.

Immunoferon (AM3) enhances the activities of early-type interferon inducers and natural killer cells

The "in vivo" effect of Immunoferon (AM3) on the production of interferon (IFN) and natural killer (NK) activity in young and old mice was studied. Although AM3 is not an IFN inducer by itself, enhancements in the serum IFN levels were produced when drug was associated to Newcastle disease virus or bacterial lipopolysaccharides as IFN inducers. This effect appeared to be dependent on the time lapsed between the inducer agent and drug. In addition, a significant stimulating effect on NK cell activity was also produced by AM3 treatments. This effect could be a consequence of a marked IFN induction and/or a modifying effect in prostaglandin synthesis.

Immunomodulatory activity of isoprinosine on experimental viral infections in avian models

The immunomodulatory activity of Isoprinosine treatments have been experimentally verified on chicken infected by three different viruses: Newcastle disease, fowl plague and avian infectious bronchitis. In protection tests, positive variations in the mean day of death rather than in the mortality rate were found depending on the modality of treatment. A stimulatory influence on primary anti-Newcastle disease virus antibody response was observed. In the avian model the Isoprinosine antiviral effect appears as due mainly to the enhancement of interferon production and to a synergistic interferon-isoprinosine interaction.

'In vivo' variations in serum interferon levels produced by antiviral compounds

The effects of adamantane, amantadine, and glucosamine on the interferon induction in chickens as compared to mice were studied. Nonviral and viral inductions were produced either by Pseudomonas aeruginosa endotoxin or by some orthomyxoviridae. After establishing their toxicity, single treatments with the drugs were intraperitoneally administered at two different doses 36, 24, and 12 h before or 2 h after the time of interferon induction. Data obtained show that adamantane and its derivative amantadine are able to inhibit the 'in vivo' interferon synthesis only when viral inductors are used; possibly by impairing the necessary stimulative action of the viral nucleic acid at the replication level. Glycosylation inhibitors like glucosamine were uneffective on interferon induction 'in vivo'.