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The objective of this study was the development of a niosomal formulation for improving skin permeation and penetration of 5-aminolevulinic acid (ALA) in the treatment of skin malignancies by photodynamic therapy (PDT). Different niosomal dispersions were prepared, using two different preparation methods. The effect of addition to a classic formulation, consisting in an equimolar Span 60-cholesterol mixture, of two different edge activators, dicethyl-phosphate (DCP) and sodium cholate (SC), and of the presence of ethanol on the vesicle properties and stability was evaluated. Selected formulations were loaded with the drug and evaluated for physicochemical and stability properties and encapsulation efficiency. Classic and elastic DCP-containing niosomes were the only formulations able to effectively incorporate the drug without instability problems. Ex vivo permeation and penetration studies through excised human skin showed that both the niosomal formulations were significantly more effective in improving ALA skin delivery than the simple aqueous drug solution commonly used in clinical practice, allowing, respectively, an increase of about 80 and 40% of the drug permeated amount and of about 100 and 50% of the drug retained into the skin. These results lead to consider the developed formulations potentially useful for improving ALA bioavailability and therapeutic effectiveness in skin malignancies treatment by topical PDT.

The fungal pathogen Candida glabrata encodes for a β-carbonic anhydrase (CA, EC 4.2.1.1), CgNce103, recently discovered. Only anions have been investigated as CgNce103 inhibitors up until now. Here we report the first sulfonamides inhibition study of this enzyme. Simple sulfonamides showed weak or moderate CgNce103 inhibitory properties, whereas acetazolamide, and a series of 4-substituted ureido-benzene-sulfonamides, sulfamates and sulfamides showed effective CgNce103 inhibitory properties, with K I s in the range of 4.1–115 nM, being also ineffective as human CA II inhibitors. As there is significant resistance of C. glabrata clinical isolates to many classical antifungal agents, inhibition of the β-CA from this organism may allow an interesting means of controlling the pathogen growth, eventually leading to antifungals with a novel mechanism of action.

Background Mycetoma is generally understood to be a chronic suppurative infection involving the skin and the underlying tissue. Mycetomas may be classified as those produced by true fungi (eumycetoma) versus those due to aerobic bacteria Actinomycetales (actinomycetoma). Methods We report the atypical case of a mycetomatoid infection of the penile shaft and glans in a 36-year-old man, originally from Senegal, affected by Takayasu’s arteritis. Results Extensive investigations excluded any other causative pathogen other than Candida albicans, and the ailment accordingly healed after fluconazole monotherapy. Conclusion The authors discuss the unusual site of the disease and the singular clinical features related to the fungal etiology and put forward considerations on the pathogenic role of common microorganisms.

A series of 2-(hydrazinocarbonyl)-3-substituted-phenyl-1H-indole-5-sulfonamides and 1-({[5-(aminosulfonyl)-3-phenyl-1H-indol-2-yl]carbonyl}amino)-2,4,6 trimethylpyridinium perchlorates possessing various 2-, 3- or 4-substituted phenyl groups with methyl-, halogeno- and methoxy-functionalities, as well as the perfluorophenyl moiety, have been evaluated as inhibitors of the beta-carbonic anhydrases (CAs, EC 4.2.1.1) from the pathogenic fungi Cryptococcus neoformans (Can2) and Candida albicans (CaNce103). Both enzymes were potently inhibited by these sulfonamides, K(I)s in the range of 4.4-118 nM against Can2, and of 5.1-128 against CaNce103, respectively. Minor structural changes in the 3-substituted phenyl moiety contribute significantly to the inhibitory activity. Some of the investigated sulfonamides showed promising selectivity ratios for inhibiting Can2 over the host, human enzymes CA I and II.

HIV fusion and entry are two steps in the viral lifecycle that can be targeted by several classes of antiviral drugs. The discovery of chemokines focused the attention on cellular co-receptors used by the virus for entering cells, and on the various steps of such processes that are subject to interactions with small molecules. Intense research has led to a wide range of effective compounds that are able to inhibit these initial steps of viral replication. All steps in the process of HIV entry into the cell may be targeted by specific compounds, grouped into three main classes (attachment inhibitors, co-receptor binding inhibitors and fusion inhibitors), which may be developed as novel antiretrovirals. Thus, several inhibitors of the gp120–CD4 interaction have been discovered (e.g., zintevir and BMS-378806). Small molecule chemokine receptor antagonists acting as HIV entry inhibitors have also been described recently, including those which interact with both the CXCR4 co-receptor (e.g., AMD3100, AMD3465, ALX40-4C, T22, T134 and T140) and CCR5 co-receptor antagonists (TAK-779, TAK-220, E913, AK-602 and NSC 651016 in clinical trials). Recently, a third family of antivirals started to be used clinically (in addition to reverse transcriptase and protease inhibitors), with the advent of enfuvirtide (T20), the first fusion inhibitor to be approved as an anti-HIV agent. Some of these compounds demonstrated in vitro synergism with other classes of antivirals, thus offering the rationale for their combination in therapies for HIV-infected individuals. Many HIV entry and fusion inhibitors are currently being investigated in controlled clinical trials, and a number of them are bioavailable as oral formulations. In 2007, the US FDA approved maraviroc as an anti-HIV agent. Maraviroc is the product of a medicinal chemistry effort initiated following identification of an imidazopyridine CCR5 ligand from a high-throughput screen of the Pfizer compound file. Maraviroc demonstrated potent antiviral activity against all CCR5-tropic HIV-1 viruses tested, including 43 primary isolates from various clades and diverse geographic origin. Maraviroc was active against 200 clinically derived HIV-1 envelope-recombinant pseudoviruses, 100 of which were derived from viruses resistant to existing drug classes. Furthermore, in October 2007, the FDA announced the approval of raltegravir for the treatment of HIV-1 infection as part of combination antiretroviral therapy in treatment-experienced patients with evidence of HIV-1 replication despite optimized background antiretroviral therapy. At present, raltegravir is the only drug in the integrase inhibitor class approved for clinical use. With the approval of raltegravir, oral agents targeting all three constitutive viral enzymes, reverse transcriptase, protease and integrase, are now represented in FDA-approved therapies.

The introduction of highly active antiretroviral therapy (HAART) in 1996 dramatically changed the course of HIV infection. This therapy involves the use of at least three agents from two distinct classes of antivirals: a protease inhibitor (PI) in combination with two nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs), or a non-nucleoside reverse transcriptase inhibitor (NNRTI) in combination with NRTIs. Nine drugs containing PIs are clinically available: the first generation ones, saquinavir, ritonavir, indinavir, nelfinavir, and amprenavir, and the second generation ones, fosamprenavir (the amprenavir prodrug), lopinavir, atazanavir, and tipranavir. Many other compounds are in advanced clinical evaluation, such as among others TMC-114, whereas a lot of different other effective HIV protease inhibitors were reported, mainly by using amprenavir and TMC-114 as lead molecules. The main goals of research in this field are: (i) the design of better pharmacological agents, devoid of severe side effects, resistance problems and with simple administration schedules (preferably once daily), and (ii) achieving eradication of the virus, and possibly, a definitive cure of the disease. A review on the pharmacology and interactions of these agents with other drugs is presented here, with emphasis on how these pharmacological interferences may improve the clinical use of antivirals, or how side effects due to PI drugs may be managed better by taking them into account (such as for example ritonavir boosting of other PIs which reduces dosages and administration schedules of these drugs). Except for being highly effective in the treatment of HIV infection, recent reports showed this class of drugs to be effective as antitumor agents, as antibacterials (for example against Mycobacterium tuberculosis infection), antifungals (against Candida albicans), antimalarials, antiSARS and anti-influenza agents.

Sulthiame, a clinically used antiepileptic, was investigated for its interaction with 12 catalytically active mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms. The drug is a potent inhibitor of CA II, VII, IX, and XII ( K I s of 6–56 nM), and a medium potency inhibitor against CA IV, VA, VB, and VI ( K I s of 81–134 nM). The high resolution crystal structure of the hCA II-sulthiame adduct revealed a large number of favorable interactions between the drug and the enzyme which explain its strong low nanomolar affinity for this isoform and may also be exploited for the design of effective inhibitors incorporating sultam moieties.

The activation of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) with l -adrenaline and histamine has been investigated by kinetic and X-ray crystallographic studies. l -Adrenaline behaves as a potent activator of isozyme CA I (activation constant of 90 nM), being a much weaker activator of isozyme CA II (activation constant of 96 μM). Isoforms CA IV, VA, VII, and XIV were activated by l -adrenaline with KAs in the range of 36–63 μM. The X-ray crystal structure of the CA II– l -adrenaline adduct revealed that the activator plugs the entrance of the active site cavity, obstructing it almost completely.

Highly active antiretroviral therapy (HAART) has dramatically changed the course of HIV infection. This therapy involves the use of at least three agents from two distinct classes of antivirals: a protease inhibitor (PI) in combination with two nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs); or a non-nucleoside reverse transcriptase inhibitor (NNRTI) in combination with NRTIs. Nine drugs containing PIs are clinically available: the first-generation saquinavir, ritonavir, indinavir, nelfinavir and amprenavir; and the second-generation fosamprenavir (the amprenavir prodrug), lopinavir, atazanavir and tipranavir. Many other compounds are in advanced clinical evaluation, such as darunavir (TMC-114) and brecanavir, among others. Many other effective HIV PIs were reported, mainly by using amprenavir and TMC-114 as lead molecules. The main goals of research in this field are: i) the design of better pharmacological agents, devoid of severe side effects, resistance problems and with simple admi...

Considerable advances have been made in the last years in the design of derivatives acting as inhibitors of HIV entry and fusion. The discovery of chemokines focused the attention on cellular coreceptors used by the virus for entering within cells, and consequently the various steps of such processes have been characterized in detail. Intense research led to a wide range of effective compounds that are able to inhibit the initial steps of HIV life cycle. All steps in the process of HIV entry into the cell may be targeted by specific compounds that may be developed as novel types of antiretrovirals. Thus, several inhibitors of the gp120-CD4 interaction have been detected so far (zintevir, FP-21399 and BMS-378806 in clinical trials). Small molecule chemokine receptor antagonists acting as HIV entry inhibitors also were described in the last period, which interact both with the CXCR4 coreceptor (such as AMD3100; AMD3465; ALX40-4C; T22, T134 and T140), or which are antagonist of the CCR5 coreceptor (TAK-779, TAK-220, SCH-C, SCH-D, E913, AK-602, UK-427857 and NSC 651016 in clinical trials), together with new types of fusion inhibitors possessing the same mechanism of action as enfuvirtide (such as T1249). Recently, a third family of antivirals started to be used clinically (in addition to the reverse transcriptase and protease inhibitors), with the advent of enfuvirtide (T20), the first fusion inhibitor to be approved as an anti-HIV agent. Some of these compounds demonstrated in vitro synergism with other classes of antivirals, offering thus the rationale for their combination in therapies for HIV-infected individuals. Many HIV entry and fusion inhibitors are currently being investigated in controlled clinical trials, and a number of them is bioavailable as oral formulations. This is an essential feature for an extended use of these compounds with the purpose of ameliorating adherence of patients to these medications and preventing the development of drug resistance.

The sulfonamides constitute an important class of drugs, with several types of pharmacological agents possessing antibacterial, anti-carbonic anhydrase, diuretic, hypoglycaemic, antithyroid, protease inhibitory and anticancer activity among others. A recently developed class of pharmacological agents incorporating primary sulfamoyl moieties in their molecule is constituted by the COX-2 selective inhibitors, with at least two clinically used drugs, celecoxib and valdecoxib. Another drug of this class, rofecoxib, does not contain sulfonamide moieties, but the isosteric and isoelectronic methylsulfone group. It was recently shown that the sulfonamide COX-2 selective inhibitors (but not the methylsulfone ones) also act as nanomolar inhibitors of several isozymes of the metallo-enzyme carbonic anhydrase (CA), some of which are strongly involved in tumourigenesis. In consequence, the potent anticancer effects of the sulfonamide COX-2 selective inhibitors and the much weaker such effects of rofecoxib, reported ultimately by many researchers, may be explained by the contribution of CA inhibition to such processes in addition to COX-2 inhibition.

By catalysing a very simple physiological reaction, the hydration of carbon dioxide (CO2) to bicarbonate (HCO3-) and a proton (H+), carbonic anhydrases (CAs), of which five genetically distinct families (α – ϵ) are presently known, are fundamental enzymes in all organisms over the phylogenetic tree. In vertebrates, including humans, the 14 different α-CA isozymes presently known are involved in a host of physiological and pathological processes and modulation of their activity by means of specific inhibitors or activators leads to important pharmacological responses. CA inhibitors (CAIs) – systemic or topically acting – are clinically used ophthalmologic drugs for the management of glaucoma, cystoid macular oedema and retinopathies of diverse nature, being used alone or in combination therapies with many other agents. Topiramate (TPM) and zonisamide are widely used antiepileptics possessing a complex mechanism of action, in which CA inhibition plays a major role. Other neurological or neuromuscular disord...

A series of positively charged sulfonamides were obtained by reaction of aminobenzolamide [5-(4-aminobenzenesulfonylamino)-1,3,4-thiadiazole-2-sulfonamide] with tri-/tetrasubstituted pyrilium salts possessing alkyl-, aryl- or combinations of alkyl and aryl groups at the pyridinium ring. The new compounds reported here were assayed for the inhibition of four physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isozymes: the cytosolic hCA I and II, the membrane-anchored bCA IV, and the membrane-bound, tumor-associated isozyme hCA IX. They showed potent inhibitory activity against all investigated isozymes, although with different profiles. For CA I the new derivatives showed inhibition constants in the range of 3-12 nM, for CA II in the range of 0.20-5.96 nM, against CA IV in the range of 2.0-10.3 nM, and against CA IX in the range of 3-45 nM, respectively. These new compounds are membrane-impermeant due to their salt-like character. Some of these derivatives were also tested for their inhibitory activity against the Cl(-)/HCO(3)(-) anion exchanger AE1: two derivatives showed inhibitory activity in the low micromolar range, whereas one compound was inactive at these concentrations. The high affinity of these new derivatives for the tumor-associated isozyme CA IX and their membrane impermeability make this type of CA inhibitor interesting candidates for the selective inhibition of only the tumor-associated isozyme and not the cytosolic ones, for which they also show high potency. Furthermore, we prove here for the first time that the CA-AE metabolon can be inhibited by the same type of sulfonamide derivative.

Multiple blue nevi have rarely been reported, and the majority of the lesions are located on the trunk and lower extremities. The blue nevus is a rare lesion on genital mucosa and may cause confusion in differential diagnosis with other pigmented lesions such as genital melanocytic macules, lentigo simplex, and malignant melanoma. Here, we describe an unusual patient who presented with a sudden onset in adulthood of multiple blue nevi on the glans penis. The epiluminescence examination revealed a substantially homogenous bluish pigmentation, which led us to favor a diagnosis of blue nevus, whereas not entirely excluding the possibility of a regressing melanoma or a metastatic melanoma. Because of the well-known diagnostic value of the blue hue in the diagnosis of malignancy by dermoscopy, a careful examination of these lesions should be made in order to minimize any risk of misclassification with melanoma.

The sulfonamides constitute an important class of drugs, with several types of pharmacological agents possessing antibacterial, anti- carbonic anhydrase, diuretic, hypoglycemic and antithyroid activity among others. A large number of structurally novel sulfonamide derivatives have ultimately been reported to show substantial antitumor activity in vitro and in vivo. Although they have a common chemical motif of aromatic/heterocyclic or amino acid sulfonamide, there are a variety of mechanisms of their antitumor action, such as carbonic anhydrase inhibition, cell cycle perturbation in the G1 phase, disruption of microtubule assembly, functional suppression of the transcriptional activator NF-Y, and angiogenesis (matrix metalloproteinase, MMP) inhibition among others. Some of these compounds selected via elaborate preclinical screenings or obtained through computer-based drug design, are currently being evaluated in clinical trials. The review summarizes recent classes of sulfonamides and related sulfonyl derivatives disclosed as effective tumor cell growth inhibitors, or for the treatment of different types of cancer. Another research line that progressed much in the last time regards different sulfonamides with remarkable antiviral activity. Thus, at least two clinically used HIV protease inhibitors possess sulfonamide moieties in their molecules, whereas a very large number of other derivatives are constantly being synthesized and evaluated in order to obtain compounds with less toxicity or activity against drug-resistant viruses. Several non nucleoside HIV reverse transcriptase or HIV integrase inhibitors containing sulfonamido groups were also reported. Another approach to inhibit the growth of retroviruses, including HIV, targets the ejection of zinc ions from critical zinc finger viral proteins, which has as a consequence the inhibition of viral replication in the absence of mutations leading to drug resistance phenotypes. Most compounds with antiviral activity possessing this mechanism of action incorporate in their molecules primary sulfonamide groups. Some small molecule chemokine antagonists acting as HIV entry inhibitors also possess sulfonamide functionalities in their scaffold.

The sulfonamides constitute an important class of drugs, with several types of pharmacological agents possessing antibacterial, anti-carbonic anhydrase, diuretic, hypoglycemic and antithyroid activity among others. A host of structurally novel sulfonamide derivatives have recently been reported to show substantial antitumor activity in vitro and / or in vivo. Although they have a common chemical motif of aromatic / heterocyclic sulfonamide, there are a variety of mechanisms of their antitumor action, such as carbonic anhydrase inhibition, cell cycle arrest in the G1 phase, disruption of microtubule assembly, functional suppression of the transcriptional activator NF-Y, and angiogenesis (matrix metalloproteinase, MMP) inhibition among others. Some of these compounds selected via elaborate preclinical screenings or obtained based on computer-aided drug design, are currently being evaluated in clinical trials. This review summarizes recent classes of sulfonamides and related sulfonyl derivatives disclosed ultimately as effective tumor cell growth inhibitors, or for the treatment of different types of cancer.

HIV entry into the cell involves the presence of at least two chemokine coreceptors, the CCR5 and CXCR4 receptors. Much research by the major drug companies has ultimately been directed to the development of small molecule chemokine antagonists that inhibit virus entry into the cell and in this way constitute novel antiviral medications. The scientific and patent literature of this highly dynamic field has been reviewed, showing that a large number of highly effective lead molecules have recently been identified, and at least one compound (the bicyclam AMD3100) has entered clinical trials as a new anti-HIV pharmacological agent. An effective chemokine antagonist with antiviral properties combined with the presently available classes of antivirals (nucleoside and non-nucleoside reverse transcriptase inhibitors (NRTIs and NNRTIs) and/or protease inhibitors (PIs)) may act synergistically in the treatment of the HIV infection, explaining the tremendous research efforts in this field.

A series of 9-sulfonylated/sulfenylated-6-mercaptopurines has been prepared by reaction of 6-mercaptopurine with sulfonyl/sulfenyl halides. These compounds constitute a new class of potent antimycobacterial agents, possessing MIC values against Mycobacterium tuberculosis H37Rv in the range of 0.39–3.39 μg/mL, as well as appreciable activity against Mycobacterium avium. Furthermore, a compound of this small series exhibited good activity (MIC under 1 μg/mL) against several drug resistant strains of M. tuberculosis.

Modification of cysteine residues in proteins, due to (i) the participation of the thiol moiety of this amino acid in oxido-reductions reactions; (ii) its ability to strongly co-ordinate transition metal ions; or (iii) its nucleophilic nature and facile reaction with electrophiles, are of critical importance in the design of novel types of pharmacological agents. Application of such procedures recently led to the design of novel antivirals, mainly based on the reaction of zinc finger proteins with disulfides and related derivatives. This approach was particularly successful for developing novel anti-HIV and anti-HPV agents. Several new anticancer therapeutic approaches, mainly targeting tubulin, Ras and farnesyl transferase among others, have also been reported, as well as the design of gastric H+/K+-ATP-ase inhibitors as anti-ulcer drugs. Other miscellaneous agents/procedures based on cysteine modification reactions are also reviewed, but have fewer applications at present. In conclusion, this unique ami...

Proteases of the serine-, cysteine- and metallo- type are widely spread in many pathogenic bacteria, where they play critical functions related to colonisation and evasion of host immune defences, acquisition of nutrients for growth and proliferation, facilitation of dissemination, or tissue damage during infection. Since all the antibiotics currently used clinically share a common mechanism of action, i.e., inhibition of bacterial cell wall biosynthesis, resistance to these pharmacological agents represents a serious medical problem, which might be resolved by using a new generation of antibiotics with a different mechanism of action. Bacterial protease inhibitors constitute an interesting possibility, due to the fact that many specific and ubiquitous proteases have recently been characterised in some detail in both Gram-positive and Gram-negative pathogens. Unfortunately, at this moment few potent, specific inhibitors for such bacterial proteases have been reported, except for signal peptidase, clostrip...

The screening of a series of arylsulfonylureido derivatives of amines (such as histamine, or dopamine), aliphatic/aromatic amino acids (such as Gly, beta-Ala, Val, Lys, Arg, Phe, Tyr, DOPA, etc.) and dipeptides (such as GlyGly, beta-AlaHis) led to the identification of three derivatives that possess tumor growth inhibitory properties against several leukemia, non-small cell lung, ovarian, melanoma, colon, CNS, renal, and breast cancer cell lines in vitro. The new derivatives were prepared by reaction of 4-toluenesulfonyl isocyanate with (protected) amines, amino acids or dipeptides. The mechanism of antitumor action with these new derivatives is not known at the moment but it may imply uncoupling of mitochondria, as for the structurally related diarylsulfonylurea sulofenur, an investigational anticancer agent.

Reaction of sulfacetamide with arylsulfonyl isocyanates afforded a series of derivatives which were used as ligands (as conjugate bases) for the preparation of metal complexes containing Ag(I) and Zn(II). The newly synthesized complexes, unlike the free ligands, act as effective antifungal agents against Aspergillus and Candida spp., some of them showing activities comparable to ketoconazole, with minimum inhibitory concentrations in the range of 0.3 – 0.5 μg/mL. The mechanism of antifungal action of these complexes seems to be not connected with the inhibition of lanosterol-14-α-demethylase, since the levels of sterols assessed in the fungi cultures were equal in the absence or in the presence of the tested compounds. Probably the new complexes act as inhibitors of phosphomannose isomerase, a key enzyme in the biosynthesis of yeast cell walls.

Aryl/alkyl-sulfonyl-, aryl/alkylcarboxyl- and aryl(sulfonyl)carbamyl/thiocarbamyl-derivatives of dibenzo-1,4-dioxine-2-acetyloxime were prepared by reaction of the title compound with sulfonyl halides, sulfonic acid anhydrides, acyl chlorides/carboxylic acids, arylsulfonyl isocyanates, aryl/acyl isocyanates or isothiocyanates. Several of the newly synthesized compounds showed effective in vitro antifungal activity against Aspergillus and Candida spp., some of them showing activities comparable to ketoconazole (with minimum inhibitory concentrations in the range of 1.2-4 microg/mL) against the two Aspergillus strains, but possessing a lower activity as compared to ketoconazole against C. albicans. Of the three investigated strains, best activity was detected against A. flavus. The mechanism of action of these compounds probably involves inhibition of ergosterol biosynthesis by interaction with lanosterol-14-alpha-demethylase (CYP51A1), since reduced amounts of ergosterol were found by means of HPLC, in cultures of the sensitive strain A. flavus treated with some of these inhibitors. Thus, the compounds reported here might possess a similar mechanism of action at molecular level with that of the widely used azole antifungals.

Sir, Keloids of the genitalia and penis are rare despite frequent surgery in this area. A careful review of the literature revealed only a few cases reported since Browne’s statement in 1949 that the skin of the penis ‘‘never forms a keloid’’ (1), and Crockett’s research attempting to classify the susceptibility of different areas of the body to keloid formation and not finding any cases affecting genitalia in a survey of 250 Sudanese natives (2). The aim of this report is to document a case that has resulted from such a common treatment as diathermy for genital warts.

Mycetoma is generally understood to be a chronic suppurative infection involving the skin and the underlying tissue. Mycetomas may be classified as those produced by true fungi (eumycetoma) versus those due to aerobic bacteria Actinomycetales (actinomycetoma).We report the atypical case of a mycetomatoid infection of the penile shaft and glans in a 36-year-old man, originally from Senegal, affected by Takayasu's arteritis.Extensive investigations excluded any other causative pathogen other than Candida albicans, and the ailment accordingly healed after fluconazole monotherapy.The authors discuss the unusual site of the disease and the singular clinical features related to the fungal etiology and put forward considerations on the pathogenic role of common microorganisms.

A β-carbonic anhydrase (CA, EC 4.2.1.1) from the fungal pathogen Malassezia globosa has been cloned, characterized, and studied for its inhibition with sulfonamides. This enzyme, designated MG-CA, has significant catalytic activity in the CO(2) hydration reaction and was inhibited by sulfonamides, sulfamates, and sulfamides with K(I) in the nanomolar to micromolar range. Several sulfonamides have also been investigated for the inhibition of growth of M. globosa, M. dermatis, M. pachydermatic, and M. furfur in cultures, whereas a mouse model of dandruff showed that treatment with sulfonamides led to fragmented fungal hyphae, as for the treatment with ketoconazole, a clinically used antifungal agent. These data prompt us to propose MG-CA as a new antidandruff drug target.

A series of 9-sulfonylated/sulfenylated-6-mercaptopurines has been prepared by reaction of 6-mercaptopurine with sulfonyl/sulfenyl halides. These compounds constitute a new class of potent antimycobacterial agents, possessing MIC values against Mycobacterium tuberculosis H37Rv in the range of 0.39–3.39 μg/mL, as well as appreciable activity against Mycobacterium avium. Furthermore, a compound of this small series exhibited good activity (MIC under 1 μg/mL) against several drug resistant strains of M. tuberculosis.

A beta-carbonic anhydrase (CA, EC 4.2.1.1), the protein encoded by the NCE103 gene of Candida glabrata which also present in Candida albicans and Saccharomycescerevisiae, was cloned, purified, characterized kinetically and investigated for its inhibition by a series simple, inorganic anions such as halogenides, pseudohalogenides, bicarbonate, carbonate, nitrate, nitrite, hydrogen sulfide, bisulfite, perchlorate, sulfate and some isosteric species. The enzyme showed significant CO(2) hydrase activity, with a k(cat) of 3.8 x 10(5)s(-1) and k(cat)/K(M) of 4.8 x 10(7)M(-1)s(-1). The Ca glabrata CA (CgCA) was moderately inhibited by metal poisons (cyanide, azide, cyanate, thiocyanate, K(I)s of 0.60-1.12 mM) but strongly inhibited by bicarbonate, nitrate, nitrite and phenylarsonic acid (K(I)s of 86-98 microM). The other anions investigated showed inhibition constants in the low millimolar range, with the exception of bromide and iodide (K(I)s of 27-42 mM).

HIV entry and fusion are two steps in the viral life cycle that can be targeted by several classes of antiviral drugs. The discovery of chemokines focused the attention on cellular coreceptors used by the virus for entering within cells, and to the various steps of such processes which are subject to interactions with small molecules. Intense research led to a wide range of effective compounds that are able to inhibit these initial steps of viral replication. All steps in the process of HIV entry into the cell may be targeted by specific compounds that may be developed as novel types of antiretrovirals. Thus, several inhibitors of the gp120-CD4 interaction have been detected so far (zintevir, FP-21399 and BMS-378806 in clinical trials). Small molecule chemokine receptor antagonists acting as HIV entry inhibitors also were described in the last period, which interact both with the CXCR4 coreceptor (such as AMD3100; AMD3465; ALX40-4C; T22, T134 and T140), or which are antagonist of the CCR5 coreceptor (TAK-779, TAK-220, SCH-C, SCH-D, E913, AK-602 and NSC 651016 in clinical trials), together with new types of fusion inhibitors possessing the same mechanism of action as enfuvirtide (such as T1249). Recently, a third family of antivirals started to be used clinically (in addition to the reverse transcriptase and protease inhibitors), with the advent of enfuvirtide (T20), the first fusion inhibitor to be approved as an anti-HIV agent. Some of these compounds demonstrated in vitro synergism with other classes of antivirals, offering thus the rationale for their combination in therapies for HIV-infected individuals. Many HIV entry and fusion inhibitors are currently investigated in controlled clinical trials, and there are a number of them that is bioavailable as oral formulations. This is an essential feature for an extended use of these compounds with the purpose of ameliorating adherence of patients to these medications and preventing the development of drug resistance.

The discovery that inhibition of phosphodiesterase-5 (PDE5) reduces the degradation of cGMP, allowing erectile function to occur by relaxation of penile smooth muscle, represents a revolutionary approach or the treatment of erectile dysfunction (ED). Three PDE5 inhibitors (sildenafil, tadalafil, and vardenafil) are clinically available at this time, and extensive drug design efforts are registered for finding agents with a better activity, enhanced selectivity and reduced side effects. Many classes of such compounds have been reported, belonging to diverse chemical entities. The drug design has been very much facilitated after the report of the X-ray crystal structure of the PDE5 catalytic domain in complex with the three clinically used derivatives. PDE5 inhibitor therapy, has been found to be effective in special clinical populations, such as those with prostate cancer, diabetes, and cardiovascular disease. The duration of action of sildenafil and vardenafil is of about 4 hours, whereas that of tadalafil is of about 36 hours, and the overall safety of the treatments is good. There is a risk of hypotension if nitrates are given concurrently with the PDE5 inhibitors. Common side-effects include headache, facial flushing, nasal congestion, dyspepsia and transient visual impairment. There are pharmacological interactions between these drugs and other medications metabolized by the cytochrome P450 (P3A4 isoform), such as the azole antifungals, erythromycin and the HIV protease inhibitors.

Anetoderma is characterized by circumscribed areas of flaccid skin caused by the loss of elastic tissue in the dermis. It may be primary or secondary to various dermatoses. The primary form has been reported in patients with autoimmune diseases, increased levels of antiphospholipid antibodies, prothrombotic abnormalities, and recently, HIV-1 disease. The origin of anetoderma remains unknown. A case of primary anetoderma is reported in a 45-year-old man with asymptomatic HIV-1 infection who was receiving antiretroviral therapy. Laboratory research included the classic immunologic investigations and screening for prothrombotic abnormalities. Possible pathogenic mechanisms of anetoderma, especially with respect to HIV-1 infection and antiretroviral therapy, are discussed.

In the anal region, pruritus may be both idiopathic (mainly of psychological/psychiatric origin) and secondary to an underlying disorder or related to local causes (mainly of dermatologic interest). Persistent pruritus ani is, in particular, a challenging experience for the dermatologist.

The inhibition of the last human carbonic anhydrase (CA, EC 4.2.1.1) isozyme (hCA XIV) discovered has been investigated with a series of sulfonamides, including some clinically used derivatives (acetazolamide, methazolamide, ethoxzolamide, dichlorophenamide, dorzolamide, brinzolamide, benzolamide, and zonisamide), as well as the sulfamate antiepileptic drug topiramate. The full-length hCA XIV is an enzyme showing a medium-low catalytic activity, quite similar to that of hCA XII, with the following kinetic parameters at 20 degrees C and pH 7.5, for the CO2 hydration reaction: k(cat) = 3.12 x 10(5) s(-1) and k(cat)/K(M) = 3.9 x 10(7) M(-1) s(-1). All types of activities have been detected for the investigated compounds, with several micromolar inhibitors, including zonisamide, topiramate, and simple sulfanilamide derivatives (K(I)-s in the range of 1.46-6.50 microM). In addition, topiramate and zonisamide were observed to behave as weak hCA XII inhibitors, while zonisamide was an effective hCA IX inhibitor (K(I) of 5.1 nM). Some benzene-1,3-disulfonamide derivatives or simple five-membered heteroaromatic sulfonamides showed K(I)-s in the range of 180-680 nM against hCA XIV, whereas the most effective of such inhibitors, including 3-chloro-/bromo-sulfanilamide, benzolamide-like, ethoxzolamide-like, and acetazolamide/methazolamide-like derivatives, showed inhibition constant in the range of 13-48 nM. The best hCA XIV inhibitor was aminobenzolamide (K(I) of 13 nM), but no CA XIV-selective derivatives were evidenced. There are important differences of affinity of these sulfonamides/sulfamates for the three transmembrane CA isozymes, with CA XII showing the highest affinity, followed by CA IX, whereas CA XIV usually showed the lowest affinity for these inhibitors.

A detailed inhibition study of five carbonic anhydrase (CA, EC 4.2.1.1) isozymes with inorganic phosphates, carbamoyl phosphate, the antiviral phosphonate foscarnet as well as formate is reported. The cytosolic isozyme hCA I was weakly inhibited by neutral phosphate, strongly inhibited by carbamoyl phosphate (K(I) of 9.4 microM), and activated by hydrogen- and dihydrogenphosphate, foscarnet and formate (best activator foscarnet, K(A)=12 microM). The cytosolic isozyme hCA II was weakly inhibited by all the investigated anions, with carbamoyl phosphate showing a K(I) of 0.31 mM. The membrane-associated isozyme hCA IV was the most sensitive to inhibition by phosphates/phosphonates, showing a K(I) of 84 nM for PO(4)(3-), of 9.8 microM for HPO(4)(2-), and of 9.9 microM for carbamoyl phosphate. Foscarnet was the best inhibitor of this isozyme (K(I) of 0.82 mM) highly abundant in the kidneys, which may explain some of the renal side effects of the drug. The mitochondrial isozyme hCA V was weakly inhibited by all phosphates/phosphonates, except carbamoyl phosphate, which showed a K(I) of 8.5 microM. Thus, CA V cannot be the isozyme involved in the carbamoyl phosphate synthetase I biosynthetic reaction, as hypothesized earlier. Furthermore, the relative resistance of CA V to inhibition by inorganic phosphates suggests an evolutionary adaptation of this mitochondrial isozyme to the presence of high concentrations of such anions in these energy-converting organelles, where high amounts of ATP are produced by ATP synthetase, from ADP and inorganic phosphates. The transmembrane, tumor-associated isozyme hCA IX was on the other hand slightly inhibited by all these anions.

An increasing number of carbonic anhydrase (CA) isozymes have been discovered in human organs. However, there is little evidence concerning their expression in mammal skin, humans included, and the isozymes involved have not been identified yet. In this study, the distribution of three CA isozymes I, II and IX in human skin from healthy subjects was investigated using an immunohistochemical technique. Specific staining for CA I and II was detected in the basolateral plasma membrane of the epithelial cells of the spinous and basal layers of epidermis as well as in the endothelium of capillaries in the papillary dermis. A marked CA II immunoreactivity was mostly found in secretory cells of the sweat glands. No signal for CA IX was detected but on the plasma membranes and the cytoplasm of cells surrounding the hair shaft. The significance and biological role of CA isozymes expression in human skin is discussed.

Multiple blue nevi have rarely been reported, and the majority of the lesions are located on the trunk and lower extremities. The blue nevus is a rare lesion on genital mucosa and may cause confusion in differential diagnosis with other pigmented lesions such as genital melanocytic macules, lentigo simplex, and malignant melanoma. Here, we describe an unusual patient who presented with a sudden onset in adulthood of multiple blue nevi on the glans penis. The epiluminescence examination revealed a substantially homogenous bluish pigmentation, which led us to favor a diagnosis of blue nevus, whereas not entirely excluding the possibility of a regressing melanoma or a metastatic melanoma. Because of the well-known diagnostic value of the blue hue in the diagnosis of malignancy by dermoscopy, a careful examination of these lesions should be made in order to minimize any risk of misclassification with melanoma.

HIV entry within the cell involves the presence of at least two chemokine co-receptors, the CCR5 and CXCR4 receptors. Viral entry can be inhibited by the natural ligands for CXCR4, the CXC chemokine SDF-1 and CCR5, the CC chemokines RANTES, MIP-1alpha and MIP-1beta, respectively. Much research has been devoted ultimately to the development of small molecule chemokine antagonists that inhibit virus entry within the cell, and constitute in this way novel antiviral medications. The most potent and specific CXCR4 antagonists reported up to now are the bicyclam derivatives, which also potently block X4 HIV replication. One such compound, AMD3100 has proved to be a highly specific CXCR4 antagonist, which consistently blocks the outgrowth of all X4 HIV and dual-tropic (R5/X4) variants that use CXCR4 for entering the cells. From such bicyclam analogues, AMD3100 was selected as the clinical candidate, which, after initial Phase I studies, proceeded to Phase II trials, but unfortunately showed significant cardiac side effects which lead to its withdrawal from further development. The first nonpeptidic compound that interacts with CCR5, but not with CXCR4, is a quaternary ammonium derivative, TAK-779, which also shows potent but variable anti-HIV activity. A large number of potent CCR5 antagonists from several classes of polycyclic derivatives have been recently disclosed. Many such derivatives showed nanomolar binding affinity to the receptor, and at least one of them, the oxime-piperidine derivative SCH-351125 has progressed to clinical evaluation. The development of such agents for clinical use may constitute an additional approach for the treatment of HIV infection, in addition to the classical one involving reverse transcriptase and protease inhibitors.

Reaction of sodium N,N-dimethyldithiocarbamate or N,N-diethyldithiocarbamate with arylsulfonyl halides afforded a series of arylsulfonyl-N,N-dialkyl-dithiocarbamates. The reactivity of these new derivatives with cysteine and glutathione has been investigated in order to identify derivatives that might label a cysteine residue of the heterodimeric protein tubulin which plays a critical physiological function in cell division and also possesses enzymatic activity as a GTP-ase. Since many antitumor drugs exert their action by binding to tubulin, inhibiting in this way microtubule association and provoking cell death, some of the most reactive compounds against the thiol reagents found in this work have been assayed for their antitumor activity. Indeed strong tumor cell growth inhibitory properties against several leukemia, non-small cell lung, ovarian, melanoma, colon, CNS, renal, prostate and breast cancer has been found in vitro for some of the 4-halogeno-, 4-methyl- or 4-carboxyphenyl-substituted arylsulfonyl-N,N-dialkyl-dithiocarbamates. Furthermore, some of these derivative were shown to act as in vitro tubulin polymerization inhibitors using a turbidimetric assay.

A series of alkyl/arylsulfonyl-N,N-diethyl-dithiocarbamates has been prepared by reaction of sodium N,N-diethyldithiocarbamate with alkyl/arylsulfonyl halides. The reactivity of these new derivatives against cysteine and glutathione has been investigated in order to identify derivatives that might label a critical cysteine residue of tubulin (Cys 239 of human β2 tubulin chain). Some of the most reactive compounds showed moderate to powerful tumor growth inhibitory properties against several leukemia, non-small cell lung, ovarian, melanoma, colon, CNS, renal, prostate and breast cancer cell lines in vitro.

Two well known antimicrobial sulfonamides, sulfadiazine and sulfamerazine were reacted with arylsulfonyl isocyanates, affording several new arylsulfonylureido derivatives. These compounds were subsequently used as ligands (in the form of conjugate bases, as sulfonamide anions) for the preparation of metal complexes containing silver and zinc. The newly synthesized complexes, unlike the free ligands, proved to act as effective antifungal agents against several Aspergillus and Candida spp., some of them showing activities comparable to ketoconazole, with minimum inhibitory concentrations in the range of 1.5-5 microg/ml. The mechanism of antifungal action of these complexes seems to be different from that of the azole antifungals acting as lanosterol-14-alpha-demethylase inhibitors. Levels of sterols assayed in the fungi cultures treated with these new antifungals were equal in the absence or in the presence of the tested compounds. This is in strong contrast with similar experiments in which ketoconazole has been used as antifungal, when drastically reduced ergosterol amounts could be detected. Thus, it is probable that the inhibition of phosphomannose isomerase, a key enzyme in the biosynthesis of yeast cell walls, imparts antifungal activity to the new metal complexes reported here.

A 20-year-old male presented with a 4 year history of a solitary nodule, 8 mm in diameter on the left temple. It was covered by normal skin, with a central depression and elevated borders. Histopathology showed numerous horn cysts amidst nests and strands of basaloid cells surrounded by a dense fibrous stroma. The clinical and histopathological features were characteristic of desmoplastic trichoepithelioma.

A 43-year-old man, who was an intravenous drug abuser from 1978 to 1988, was referred to our STD & AIDS Center in October 1995 with flesh-colored nodules of the foreskin. He was confirmed to be seronegative in February 1989, and the first positive human immunodeficiency virus (HIV) serology was documented in October 1989. At that time, the CD4+ count was 114/mm3 and anti-retroviral therapy was therefore initiated and prolonged until October 1995. Within the last 4 months, the patient progressively lost weight (13 kg) and suffered from recurrent oral candidiasis, cytomegalovirus (CMV) retinitis, and severe oral herpes simplex virus (HSV) infection. Shortly afterwards the dermatologic lesions appeared. At this time, the CD4+ count had decreased to 8/mm3. Examination revealed nodules distributed over the external and internal linings of the foreskin, some isolated and some grouped, but individually well defined. These lesions, of the same color as the surrounding skin or slightly erythematous, were of varying sizes ranging from 0.5 to 1 cm in diameter, sessile, globous, coated with a keratotic epidermal layer, not shiny, hard-elastic, non-tender at compression, and without evident central umbilication, mimicking condylomata acuminata (Fig. 1). Upon squeezing, no discharge could be seen. The source of this infection was not identified as the patient denied sexual contact for the previous year. A three-lesions biopsy showed the characteristic histologic features of molluscum contagiosum (MC). The dermis appeared indented by multiple, closely packed, lobules of proliferating epithelium (Figs 2 and 3). The infected keratinocytes contained intracytoplasmatic inclusions, the so-called molluscum bodies displacing the nucleus and enlarging the infected cells.

Summary: The aim of this work was to confirm our preliminary clinical and immunological evaluation of the protective effects of a herpes simplex virus (HSV) vaccine derived from killed virus in the treatment of relapsing facial or genital herpes simplex infection. A total of 142 patients were treated with the HSV vaccine and a control group of 50 were treated with intermittent oral acyclovir (ACV). The vaccine reduced annual active disease days in vaccinees to 11.59 (±15.3) after treatment (65.11±31.64 before treatment) compared to 30.4±17.49 days after treatment of the control group patients (71.86±32.5 before treatment).

Antonio Mastrolorenzo, Luana Tiradritti, Umberto Locunto, Marco Carini, Daniela Massi and Giuliano Zuccati Dipartimento di Scienze Dermatologiche, Universita degli Studi di Firenze, Via degli Alfani, 37, IT-50121 Firenze, Unita Operativa di Urologia, Universita degli Studi di Firenze, Ospedale Santa Maria Annunziata, Bagno a Ripoli and Dipartimento di Patologia Umana e Oncologica, Universita degli Studi di Firenze, Firenze, Italy. E-mail: amas@dada.it Accepted October 15, 2004.