The analysis of 51 genes in DSM-IV combined type attention deficit hyperactivity disorder: association signals in DRD4, DAT1 and 16 other genes

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder, starting in early childhood and persisting into adulthood in the majority of cases. Family and twin studies have demonstrated the importance of genetic factors and candidate gene association studies have identified several loci that exert small but significant effects on ADHD. To provide further clarification of reported associations and identify novel associated genes, we examined 1,038 single-nucleotide polymorphisms (SNPs) spanning 51 candidate genes involved in the regulation of neurotransmitter pathways, particularly dopamine, norepinephrine and serotonin pathways, in addition to circadian rhythm genes. Analysis used within family tests of association in a sample of 776 DSM-IV ADHD combined type cases ascertained for the International Multi-centre ADHD Gene project. We found nominal significance with one or more SNPs in 18 genes, including the two most replicated findings in the literature: DRD4 and DAT1. Gene-wide tests, adjusted for the number of SNPs analysed in each gene, identified associations with TPH2, ARRB2, SYP, DAT1, ADRB2, HES1, MAOA and PNMT. Further studies will be needed to confirm or refute the observed associations and their generalisability to other samples.

Pyoderma gangrenosum: an updated review

Pyoderma gangrenosum is a rare, ulcerative, cutaneous condition. First described in 1930, the pathogenesis of pyoderma gangrenosum remains unknown, but it is probably related to a hyperergic reaction. There are various clinical and histological variants of this disorder. Pyoderma gangrenosum often occurs in association with a systemic disease such as inflammatory bowel disease, rheumatologic disease, paraproteinaemia, or haematological malignancy. The diagnosis, mainly based on the clinical presentation and course, is confirmed through a process of elimination of other causes of cutaneous ulcers. Local treatment may be sufficient for mild disease, while for severe cases, systemic immunosuppressants are the mainstay. Long-term treatment with these agents is often required, but this can expose patients to adverse side-effects.

The influence of thalidomide on the clinical and immunologic manifestation of erythema nodosum leprosum

Immunologic and clinical manifestations of erythema nodosum leprosum (ENL) and their response to thalidomide therapy were evaluated. Circulating tumor necrosis factor-alpha (TNF alpha) levels were assayed in serum obtained from lepromatous leprosy patients at diagnosis, during multidrug therapy, at the onset of ENL episodes, and during treatment with thalidomide. Patients with systemic ENL demonstrated the highest serum TNF alpha levels, which decreased significantly during thalidomide treatment. Serum TNF alpha in nonreactional patients was associated with mild flu-like symptoms and local inflammatory lesions. Serum interferon-gamma (IFN-gamma) was also elevated in patients with high TNF alpha levels. Thalidomide therapy reduced not only serum TNF alpha levels and the clinical symptoms but also the dermal infiltration of polymorphonuclear leukocytes and T cells. The expression of intercellular adhesion molecule 1 and major histocompatibility complex class II antigens on the epidermal keratinocytes was also down-regulated. These results indicate that the thalidomide-induced alleviation of clinical symptoms of ENL was associated with a reduction of TNF alpha levels.

Natural evolution of skin test sensitivity in patients allergic to beta-lactam antibiotics

BACKGROUND

Subjects with immediate reactions to penicillins and positive skin test responses may lose sensitivity if penicillin is avoided. The longer the interval between the reaction and the skin test, the greater the likelihood of having a negative result.

OBJECTIVE

We sought to study prospectively the evolution of skin test sensitivity in a group of subjects allergic to penicillin with positive skin test responses to different penicillin determinants.

METHODS

Skin tests were performed with major and minor determinants of benzylpenicillin (BPO/MDM), amoxicillin (AX), and ampicillin at the initial evaluation and repeated 1, 3, and 5 years later if the responses were still positive. Subjects were divided into 2 groups. Group A consisted of patients with a positive skin test response to benzylpenicilloyl or minor determinant mixture, and group B consisted of those with a selective response to amoxicillin and good tolerance to benzylpenicillin.

RESULTS

In group A (n = 31) after 1 year, 25 patients continued to have positive responses and 6 began to have negative responses; after 3 years, 18 continued to have positive responses, 5 began to have negative responses, and 2 were lost to follow-up; and after 5 years, 12 continued to have positive responses, 5 began to have negative responses, and 1 was lost to follow-up. In group B (n = 24) 12 had positive responses, and 12 had negative responses after 1 year; 6 had positive responses, 5 had negative responses, and 1 was lost to follow-up after 3 years; and no patients had positive responses, 5 had negative responses, and 1 was lost to follow-up after 5 years. Survival analysis showed significant differences between groups (log-rank test = 12.8; P <. 0003).

CONCLUSION

Patients with a selective response to amoxicillin tended to lose sensitivity faster than those who responded to several penicillin determinants, supporting the existence of at least 2 distinct types of IgE response in patients allergic to beta-lactam.

Reduced olfactory performance in patients with major depression

The aim of the present study is to investigate olfactory sensitivity and odor evaluations in a homogeneous sample of unipolar depressive patients using pure olfactory odors. Twenty-four in-patients with major depressive disorder (MDD) were investigated during their acute depressive phase. Eighteen of them participated a second time after successful treatment. A group of healthy subjects, matched by age, sex, and smoking behavior, served as a control. Olfactory sensitivity, as measured by threshold tests, was strongly reduced in patients with severe depression. Additional correlative analyses revealed that the lowered sensitivity could partly be predicted by high depression scores. After successful medical treatment, these sensitivity differences were reduced and did not reach the significance level. The subjective odor evaluations (valence and intensity ratings) were not markedly changed in general. The results reveal that olfactory performance in MDD patients is reduced at an early perceptional level of stimulus processing. It is discussed whether this effect can be attributed to the close functional connection between the main olfactory bulb and the amygdala.

Allergy to penicillin with good tolerance to other penicillins; study of the incidence in subjects allergic to beta-lactams

Two hundred and eighty-eight subjects with a history of allergy to penicillin were studied for objective proof of their allergy. On the basis of skin tests, specific IgE antibody measurements and direct challenge tests. 64 patients (22%) were shown objectively to be allergic to one or more penicillins. The following tests were carried out: skin tests to benzyl-penicilloyl poly-L-lysine (BPO-PLL), minor determinant mixture (MDM), amoxycillin (AX) and ampicillin (AMP), in-vitro IgE antibody measurement to benzyl-penicilloyl (BPO) and AX and challenge with benzylpenicillin (BP), phenoxy-methyl-penicillin (PV) and amoxycillin. Forty-four cases were found to respond to benzyl or phenoxymethyl-penicillin, however, 20 were shown to be sensitive to amoxycillin and unresponsive to tests with other penicillins. The contribution that any individual test gave for establishing the diagnosis was 21.8% for skin testing with BPO-PLL, 9.3% with MDM and 12.5% with AX. Nine point three per cent were RAST positive to BPO and 1.5% to AX; 7.8% developed a positive response after challenge to BP, 7.8% to PV and 14% to AX. In 16% of the 64 positive cases more than one test was found to be positive. The challenge tests suggested that not all the penicillin-sensitive subjects had IgE-mediated reactions implying other immunological mechanisms. These results clearly demonstrate the importance of side chain-specific diagnostic reagents and challenge tests. Thirty-one per cent of the positive group or 6.9% of the total group would have been missed in this study using benzyl or phenoxymethyl-penicillin diagnostic reagents alone.

Antimicrobial activity of a bovine hemoglobin fragment in the tick Boophilus microplus

Antifungal and antibacterial activities were detected in the hemolymph and gut contents of the cattle tick, Boophilus microplus. A peptide with antibacterial activity from the tick gut contents was purified to homogeneity by reversed-phase chromatography. The molecular mass of the purified peptide was 3,205.7 Da, measured by matrix-assisted laser desorption/ionization mass spectrometry. The amino acid sequence was obtained by Edman degradation and showed that the peptide was identical to a fragment of the bovine alpha-hemoglobin. A synthetic peptide based on the sequence obtained showed characterization data identical to those of the isolated material, confirming its structure. The synthetic peptide was active in micromolar concentrations against Gram-positive bacteria and fungi. These data led us to conclude that the antibacterial activity detected in tick gut contents is the result of enzymatic processing of a host protein, hemoglobin. This activity may be used by ticks as a defense against microorganisms.

The role of transient receptor potential vanilloid 1 in mechanical and chemical visceral hyperalgesia following experimental colitis

The transient receptor potential vanilloid 1 receptor (TRPV1) is an important nociceptor involved in neurogenic inflammation. We aimed to examine the role of TRPV1 in experimental colitis and in the development of visceral hypersensitivity to mechanical and chemical stimulation. Male Sprague-Dawley rats received a single dose of trinitrobenzenesulfonic acid (TNBS) in the distal colon. In the preemptive group, rats received the TRPV1 receptor antagonist JYL1421 (10 mumol/kg, i.v.) or vehicle 15 min prior to TNBS followed by daily doses for 7 days. In the post-inflammation group, rats received JYL1421 daily for 7 days starting on day 7 following TNBS. The visceromotor response (VMR) to colorectal distension (CRD), intraluminal capsaicin, capsaicin vehicle (pH 6.7) or acidic saline (pH 5.0) was assessed in all groups and compared with controls and naïve rats. Colon inflammation was evaluated with H&E staining and myeloperoxidase (MPO) activity. TRPV1 immunoreactivity was assessed in the thoraco-lumbar (TL) and lumbo-sacral (LS) dorsal root ganglia (DRG) neurons. In the preemptive vehicle group, TNBS resulted in a significant increase in the VMR to CRD, intraluminal capsaicin and acidic saline compared the JYL1421-treated group (P<0.05). Absence of microscopic colitis and significantly reduced MPO activity was also evident compared with vehicle-treated rats (P<0.05). TRPV1 immunoreactivity in the TL (69.1+/-4.6%) and LS (66.4+/-4.2%) DRG in vehicle-treated rats was increased following TNBS but significantly lower in the preemptive JYL1421-treated group (28.6+/-3.9 and 32.3+/-2.3 respectively, P<0.05). JYL1421 in the post-inflammation group improved microscopic colitis and significantly decreased the VMR to CRD compared with vehicle (P<0.05, >/=30 mm Hg) but had no effect on the VMR to chemical stimulation. TRPV1 immunoreactivity in the TL and LS DRG was no different from vehicle or naïve controls. These results suggest an important role for TRPV1 channel in the development of inflammation and subsequent mechanical and chemical visceral hyperalgesia.

Comparison of risk patterns in carcinoma and melanoma of the skin in men: a multi-centre case-case-control study

We directly compared risk factors between 214 histologically confirmed melanomas (CMM), 215 basal-cell carcinomas (BCC) and 139 squamous-cell carcinomas (SCC) in a multiple case-case-control study with 349 controls from patients without dermatological disease admitted to the same hospitals. Subjects with fair hair had a significant risk increase for all types of tumours at a comparable level (OR(adj) for blonde hair: CMM 2.3; SCC 2.4; BCC 2.3). The effect of pale eyes was significant and similar for CMM and BCC (OR(adj) 2.6). Intermittent sun exposure measured in hours spent at beach during holidays was significant for both CMM (OR(adj) 2.6 for more than 7000 lifelong hours) and BCC (OR(adj) 2.1 for more than 7000 lifelong hours), while SCC exhibited a significant risk increase for chronic exposure to sunlight measured in hours of outdoor work (OR(adj) 2.2 for more than 6000 lifelong hours). In the case-case comparison using a multinomial logistic regression model, we found a statistically significant risk difference for pale eyes, and number of naevi in the CMM group, compared to other skin cancers. For intermittent sun exposure, there was a significant risk difference of BCC when compared to the risk of SCC. Factors influencing risk of SCC are different, with chronic exposure to sun playing a major role in causing this type of carcinoma.

Cross-reactivity between penicillins and cephalosporins: clinical and immunologic studies

Nineteen well-characterized penicillin-allergic patients were investigated for their sensitivity to cephalosporins containing potentially cross-reactive side chains. All patients were administered cephamandole parenterally and, if this was tolerated, a course of oral cephaloridine was administered. Only two patients responded to the cephamandole; none of the remaining patients reacted to cephaloridine. Benzylpenicilloyl RAST-inhibition studies with sera from three subjects who had not reacted to the cephalosporins demonstrated that cephamandole linked to proteins was capable of recognizing benzylpenicilloyl-specific IgE antibody. It is concluded that consideration of side chain structures can help to predict possible cross-reactions between penicillins and cephalosporins, but carefully controlled challenge tests are advisable before penicillin-allergic patients are treated with cephalosporins. In relation to cross-reacting potential, in vitro experimental studies are difficult to interpret and may in some circumstances overestimate the risk.

Cross-reactivity between a penicillin and a cephalosporin with the same side chain

BACKGROUND

The cross-reactivity between penicillins and cephalosporins can be influenced by different factors, which are not all well known. The chemical structure of the side chain may contribute to the cross-reactivity.

OBJECTIVE

The study was carried out in allergic subjects who are selectively responsive to amoxicillin to determine allergenic cross-reactivity with a cephalosporin containing a side chain identical to that of amoxicillin, cefadroxil, and one containing a different side chain, cefamandole.

METHODS

Allergic subjects with a selective response to amoxicillin were chosen according to the following criteria: history of an immediate allergic reaction to amoxicillin, negative skin test responses to benzylpenicilloyl and minor determinant mixture of benzylpenicillin, negative RAST response to benzylpenicilloyl, and good tolerance to benzylpenicillin and phenoxymethyl penicillin challenges. In addition, subjects had to have a positive skin test response to amoxicillin and/or positive RAST response to amoxicilloyl or, if these test results were negative, a positive challenge test response to amoxicillin. In vivo cross-reactivity to cefadroxil was assessed by giving oral cefadroxil at increasing doses from 5 to 500 mg. In vitro cross-reactivity was determined by RAST inhibition studies with amoxicilloyl RAST disks and the following monomeric conjugates in the fluid phase: amoxicillin-butylamine, cefadroxil-butylamine, and the side chain para-hydroxy-phenylglycine. Tolerance to cefamandole was determined by giving 100 mg and then 500 mg parenterally.

RESULTS

Twenty-one patients with a selective response to amoxicillin were included in the study. Eight subjects (38%) had a positive response to cefadroxil, and none reacted to cefamandole. In vitro RAST inhibition studies indicated that cefadroxil-butylamine monomers cross-reacted with amoxicillin butylamine and the side chain contributed relevantly to the inhibition.

CONCLUSIONS

These results indicate that the percentage of cross-reactivity between penicillins and cephalosporins with an identical side chain is high and that this critical part of the molecule seems to be an important contributor to these results. The value is higher than previously reported data from similar studies of non-side-chain-related cephalosporins.

Polymerase chain reaction for diagnosis of enterohemorrhagic Escherichia coli infection and hemolytic-uremic syndrome

Two pairs of oligonucleotide primers were designed to amplify fragments of the genes for Shiga-like toxin I (SLT-I) and SLT-II in a single reaction. A 370-bp segment and a 283-bp segment were amplified for SLT-I and SLT-II, respectively. The specificities of the polymerase chain reaction (PCR) amplification products were confirmed by using radioactively labeled oligonucleotide probes. SLT sequences were amplified from DNA isolated from 13 previously characterized enterohemorrhagic Escherichia coli (EHEC) strains. No amplification product was produced by using DNA from 20 non-EHEC strains. As little as one bacterial genome was detectable. PCR was then applied to DNA isolated directly from stool samples. We had to remove inhibitors of PCR that were present in lysates prepared from stool samples before amplification was achieved. First, we evaluated the sensitivity of PCR for the detection of known numbers of EHEC added to normal stools. Second, three children with SLT in their stools were shown to have SLT sequences in their stools by PCR. Two of these children had hemolytic-uremic syndrome, and a third child was asymptomatic. Stool specimens collected from another 26 asymptomatic children were negative by PCR for SLT sequences. PCR can be used to diagnose EHEC infections without prior culture of stool specimens.

Liver cirrhosis is reverted by urokinase-type plasminogen activator gene therapy

Liver cirrhosis represents a worldwide health problem and is a major cause of mortality. Cirrhosis is the result of extensive hepatocyte death and fibrosis induced by chronic alcohol abuse and hepatitis B and C viruses. Successful gene therapy approaches to this disease may require both reversal of fibrosis and stimulation of hepatocyte growth. Urokinase-type plasminogen activator (uPA) may serve this function, as it is an initiator of the matrix proteolysis cascade and induces hepatocyte growth factor expression. In a rat cirrhosis model, a single iv administration of a replication-deficient adenoviral vector encoding a nonsecreted form of human uPA resulted in high production of functional uPA protein in the liver. This led to induction of collagenase expression and reversal of fibrosis with concomitant hepatocyte and improved liver function. Thus, uPA gene therapy may be an effective strategy for treating cirrhosis in humans.

Nonimmediate reactions to betalactams: prevalence and role of the different penicillins

In patients treated with penicillins, adverse cutaneous reactions can occur within minutes or may take several days to develop. IgE antibody-mediated reactions are well documented, but other mechanisms may also be involved. In particular, nonimmediate reactions have not been studied extensively, and the purpose of the present work was to establish the incidence of such reactions among a large group of patients and to study the penicillins involved. A total of 380 subjects with a history of a cutaneous reaction following administration of a penicillin antibiotic was included in the study. Skin tests and specific IgE measurements (RAST) were carried out using various penicillins and penicillin-related reagents, and patients were also challenged with various penicillins. In some patients with delayed skin test responses, skin biopsies were carried out. The tests confirmed that 74 subjects (19.4% of total investigated) had suffered a cutaneous reaction to a penicillin derivative, and 29 of these subjects (7.6% of total or 39% of confirmed) showed evidence of having suffered a nonimmediate reaction. The latter group were identified by giving a positive delayed direct challenge, and in 65% of the cases a delayed skin test response was detected. In most cases, these responses were to amino penicillins. Skin biopsies showed a lymphomonocytic cell infiltrate. Nonimmediate reactions to penicillins are a reproducible phenomenon, suggesting that a specific mechanism is responsible. By direct challenge, 93% of responders were positive to amino penicillins (10.3% ampicillin, 82.7% amoxicillin), indicating a major role for these penicillins in nonimmediate reactions.(ABSTRACT TRUNCATED AT 250 WORDS)

Anaphylaxis to amoxycillin but good tolerance for benzyl penicillin. In vivo and in vitro studies of specific IgE antibodies

Three patients are reported on who suffered anaphylactic reactions after amoxycillin (AX) treatment and challenge but tolerated benzylpenicillin (BP) parenterally and orally. Two of the three patients had positive skin tests and RAST to AX reagents but negative responses to benzyl penicilloyl (BPO) specific skin tests and RAST and the minor determinant mixture (MDM) skin test reagent. The third case was negative to all skin tests and RAST. RAST and RAST inhibition on the two positive sera suggest that the response is related to the acyl side chain of AX.

Cirrhotic rat livers with extensive fibrosis can be safely transduced with clinical-grade adenoviral vectors. Evidence of cirrhosis reversion

Adenoviral vectors efficiently target normal liver cells; however, a clear-cut description of the safety boundaries for using adenovectors in hepatic cirrhosis has not been settled. With this in mind, we used a first-generation, replication-deficient adenoviral vector carrying the E. coli lacZ gene (Ad5betaGal) to monitor therapeutic range, biodistribution, toxicity and transduction efficiency in Wistar rats made cirrhotic by two different experimental approaches resembling alcoholic cirrhosis and biliary cirrhosis in humans. Further, we show proof of concept on fibrosis reversion by a 'therapeutic' Ad-vector (AdMMP8) carrying a gene coding for a collagen-degrading enzyme. Dose-response experiments with Ad5betaGal ranging from 1 x 10(8)-3 x 10(12) viral particles (vp) per rat (250 g), demonstrated that adenovirus-mediated gene transfer via iliac vein at 3 x 10(11 )vp/rat, resulted in an approximately 40% transduction in livers of rats made cirrhotic by chronic intoxication with carbon tetrachloride, compared with approximately 80% in control non-cirrhotic livers. In rats made cirrhotic by bile-duct obstruction only, 10% efficiency of transduction was observed. Biodistribution analyses showed that vector expression was detected primarily in liver and at a low level in spleen and kidney. Although there was an important increase in liver enzymes between the first 48 h after adenovirus injection in cirrhotic animals compared to non-transduced cirrhotic rats, this hepatic damage was resolved after 72-96 h. Then, the cDNA for neutrophil collagenase, also known as Matrix Metalloproteinase 8 (MMP8), was cloned in an Ad-vector and delivered to cirrhotic rat livers being able to reverse fibrosis in 44%. This study demonstrates the potential use of adenoviral vectors in safe transient gene therapy strategies for human liver cirrhosis.

An association study of bipolar mood disorder (type I) with the 5-HTTLPR serotonin transporter polymorphism in a human population isolate from Colombia

The short variant of a functional length polymorphism in the promoter region of the serotonin transporter has been associated with several behavioural and psychiatric traits, including bipolar mood disorder. The same short allele has also been implicated as a modifier of the bipolar phenotype. Here we evaluate the etiologic/modifier role of this polymorphism in a case (N=103) / control (N=112) sample for bipolar mood disorder (type I) collected from an isolated South American population. We did not detect an association between bipolar disorder and the 5-HTT promoter polymorphism in this sample. However, an excess of the short allele was seen in younger cases and in cases with psychotic symptoms. When combined with data from the literature, the increased frequency of the short allele in patients with psychotic symptoms was statistically significant.

Olfactory discrimination of female reproductive status by male tilapia(Oreochromis mossambicus)

The current study investigated whether discrimination of sexual status of female tilapia by males is mediated by olfaction. Size-matched groups of female tilapia were assigned as pre- or post-ovulatory according to the time since their last ovulation (15-19 days pre-ovulatory, N=7; 1-3 days post-ovulatory, N=8). Female-conditioned water and body fluids(urine, bile, faeces and plasma) were assessed for olfactory potency in males by recording the electro-olfactogram (EOG). Water extracts, urine and faeces from pre-ovulatory females all evoked significantly larger amplitude EOGs in male fish (N=6), with correspondingly lower thresholds of detection,than those from post-ovulatory females. Plasma and bile evoked very large amplitude EOGs in males but with no differences between the two groups of females. Anosmic males (N=6) did not behave differently towards pre-or post-ovulatory females, while sham-operated males (N=6) showed a marked increase in urination rate towards pre-ovulatory females. We conclude that the ability of male tilapia to discriminate between females of differing reproductive status is mediated by odorants released into the water, probably via the urine and faeces, by pre-ovulatory females.

Helicobacter pylori second-line rescue therapy with levofloxacin- and bismuth-containing quadruple therapy, after failure of standard triple or non-bismuth quadruple treatments

BACKGROUND

The most commonly used second-line Helicobacter pylori eradication regimens are bismuth-containing quadruple therapy and levofloxacin-containing triple therapy, both offering suboptimal results. Combining bismuth and levofloxacin may enhance the efficacy of rescue eradication regimens.

AIMS

To evaluate the efficacy and tolerability of a second-line quadruple regimen containing levofloxacin and bismuth in patients whose previous H. pylori eradication treatment failed.

METHODS

This was a prospective multicenter study including patients in whom a standard triple therapy (PPI-clarithromycin-amoxicillin) or a non-bismuth quadruple therapy (PPI-clarithromycin-amoxicillin-metronidazole, either sequential or concomitant) had failed. Esomeprazole (40 mg b.d.), amoxicillin (1 g b.d.), levofloxacin (500 mg o.d.) and bismuth (240 mg b.d.) was prescribed for 14 days. Eradication was confirmed by (13) C-urea breath test. Compliance was determined through questioning and recovery of empty medication envelopes. Incidence of adverse effects was evaluated by questionnaires.

RESULTS

200 patients were included consecutively (mean age 47 years, 67% women, 13% ulcer). Previous failed therapy included: standard clarithromycin triple therapy (131 patients), sequential (32) and concomitant (37). A total of 96% took all medications correctly. Per-protocol and intention-to-treat eradication rates were 91.1% (95%CI = 87-95%) and 90% (95%CI = 86-94%). Cure rates were similar regardless of previous (failed) treatment or country of origin. Adverse effects were reported in 46% of patients, most commonly nausea (17%) and diarrhoea (16%); 3% were intense but none was serious.

CONCLUSIONS

Fourteen-day bismuth- and levofloxacin-containing quadruple therapy is an effective (≥90% cure rate), simple and safe second-line strategy in patients whose previous standard triple or non-bismuth quadruple (sequential or concomitant) therapies have failed.

Helicobacter pylori infection but not small intestinal bacterial overgrowth may play a pathogenic role in rosacea

BACKGROUND AND AIMS

Recent studies suggest a potential relationship between rosacea and Helicobacter pylori (H. pylori) infection or small intestinal bacterial overgrowth (SIBO), but there is no firm evidence of an association between rosacea and H. pylori infection or SIBO. We performed a prospective study to assess the prevalence of H. pylori infection and/or SIBO in patients with rosacea and evaluated the effect of H. pylori or SIBO eradication on rosacea.

METHODS

We enrolled 90 patients with rosacea from January 2012 to January 2013 and a control group consisting of 90 patients referred to us because of mapping of nevi during the same period. We used the (13)C Urea Breath Test and H. pylori stool antigen (HpSA) test to assess H. pylori infection and the glucose breath test to assess SIBO. Patients infected by H. pylori were treated with clarithromycin-containing sequential therapy. Patients positive for SIBO were treated with rifaximin.

RESULTS

We found that 44/90 (48.9%) patients with rosacea and 24/90 (26.7%) control subjects were infected with H. pylori (p = 0.003). Moreover, 9/90 (10%) patients with rosacea and 7/90 (7.8%) subjects in the control group had SIBO (p = 0.6). Within 10 weeks from the end of antibiotic therapy, the skin lesions of rosacea disappeared or decreased markedly in 35/36 (97.2%) patients after eradication of H. pylori and in 3/8 (37.5%) patients who did not eradicate the infection (p < 0.0001). Rosacea skin lesions decreased markedly in 6/7 (85.7%) after eradication of SIBO whereas of the two patients who did not eradicate SIBO, one (50%) showed an improvement in rosacea (p = 0.284).

CONCLUSIONS

Prevalence of H. pylori infection was significantly higher in patients with rosacea than control group, whereas SIBO prevalence was comparable between the two groups. Eradication of H. pylori infection led to a significant improvement of skin symptoms in rosacea patients.

Studies of the specificities of IgE antibodies found in sera from subjects with allergic reactions to penicillins

Penicillins are immunogenic when administered to humans and in some instances they can also be allergenic, inducing specific IgE antibodies. Whilst the major haptenic group, the penicilloyl, is well characterised, less is known about the relative importance of the different parts of the structure for antibody binding and how this can influence the specificity of patients response. In order to investigate this further, sera from subjects who had suffered an IgE-mediated reaction to penicillins were studied using the radioallergosorbent test (RAST) and RAST inhibition. The assays employed reagents related to the penicillins causing the reaction. Using 173 sera, positive RAST results were only found with reagents based on benzyl penicillin (BP) and amoxicillin (AX). Fifty-three positive sera were selected for further studies and categorized into three groups: (A) sera only RAST positive to AX, (B) sera only positive to BP and (C) sera positive to both penicillins. RAST inhibition studies were then carried out using monomeric penicilloyl conjugates and compounds representing parts of the penicilloyl structures of BP and AX. For all three groups, monomeric penicilloyl conjugates were the most efficient inhibitors but there were differences for the other compounds. Group A sera were also inhibited by the side chain amoxicillin, whereas group B sera were poorly inhibited by all other inhibitors. Group C sera showed two patterns of inhibition, both consistent with their more cross-reactive profile.

McArdle disease: the mystery of reappearing phosphorylase activity in muscle culture--a fetal isoenzyme

To understand the apparently paradoxical appearance of phosphorylase in muscle cultured from patients with McArdle disease, the enzyme in muscle culture was studied immunologically and electrophoretically. Antibody against normal human muscle phosphorylase completely inhibited the enzyme of adult muscle, but it had no effect on phosphorylase activity of muscle cultures from normal individuals or patients with McArdle disease. Also, amounts of antibody that would completely inhibit phosphorylase in mature muscle left about 30% of the activity in muscle obtained from human fetus at four months' gestation. Acrylamide-disc and slab-gel electrophoresis showed a single band of phorphorylase activity in adult muscle and two bands in fetal muscle. This suggested that at four months' gestation, both fetal and mature forms are present but that only the mature isoenzyme is inhibited by the antibody. The enzyme from cultured muscle gave only a single band, with the electrophoretic mobility of the fetal isoenzyme. These data suggest that phosphorylase activity in muscle cultured from patients with McArdle disease is due to a fetal isoenzyme whose genetic control is different from that of the mature enzyme.

Conformationally restricted competitive antagonists of human/rat corticotropin-releasing factor

Corticotropin releasing factor (CRF) is a 41-peptide amide which stimulates the release of ACTH (Vale et al. Science 1981, 213, 1394). CRF has been postulated to assume an alpha-helical conformation upon binding to its pituitary receptor (Hernandez et al. J. Med. Chem. 1993, 36, 2860). We have exploited this hypothesis in the design of a limited series of cyclic analogues and have taken into consideration the effects of side-chain deletion (Alanine scan, Kornreich et al. J. Med. Chem. 1992, 35, 1870) as well as of changes in chirality (Rivier et al. J. Med. Chem. 1993, 36, 2851), with the rationale that side chains necessary for binding could also be replaced by side-chain bridges. In particular, we have used computer modeling to predict likely side chain bridging opportunities and evaluated the effects of such replacements by correlating biological results with those derived from CD spectroscopy. We have synthesized 38 monocyclic peptide amides, competitive antagonists of human/rat CRF, using solid-phase methodology on MBHA resin. After purification by preparative RP-HPLC, the peptides were analyzed by RP-HPLC and capillary zone electrophoresis and characterized by mass spectroscopy and amino acid analysis. CRF antagonists were tested for their ability to interfere with CRF-induced release of ACTH by rat anterior pituitary cells. In most cases, one of the bridge heads was located at a position where substitution by a D-residue was tolerated (i.e., positions 12 and 20). It has become clear that careful optimization of bridge length and chirality is critical. This is best exemplified by the fact that out of the 38 analogues that were synthesized and tested, only two, [cyclo(20-23)[DPhe12,Glu20,Lys23, Nle21,38]h/rCRF12-41 and cyclo(20-23)[DPhe12,Glu20,Orn23,Nle21,38] h/rCRF12-41], were found to be more potent (3 and 2 times, respectively) than [DPhe12,Nle21,38]h/rCRF12-41, the parent compound. Six analogues belonging to two different families were found to be half as potent as the standard, 18 had 2-20% of the potency of the standard, and the others were significantly less potent. CD results of all analogues in 50% TFE (a concentration of TFE that induced nearly maximum helicity of [DPhe12,Nle21,38]h/rCRF12-41) suggest that while helicity may be an important factor for CRF analogue recognition, little correlation is found between percent helicity as determined by spectral deconvolution and biological activity in vitro.

A high-density SNP linkage scan with 142 combined subtype ADHD sib pairs identifies linkage regions on chromosomes 9 and 16

As part of the International Multi-centre ADHD Genetics project we completed an affected sibling pair study of 142 narrowly defined Diagnostic and Statistical Manual of Mental Disorders, fourth edition combined type attention deficit hyperactivity disorder (ADHD) proband-sibling pairs. No linkage was observed on the most established ADHD-linked genomic regions of 5p and 17p. We found suggestive linkage signals on chromosomes 9 and 16, respectively, with the highest multipoint nonparametric linkage signal on chromosome 16q23 at 99 cM (log of the odds, LOD=3.1) overlapping data published from the previous UCLA (University of California, Los Angeles) (LOD>1, approximately 95 cM) and Dutch (LOD>1, approximately 100 cM) studies. The second highest peak in this study was on chromosome 9q22 at 90 cM (LOD=2.13); both the previous UCLA and German studies also found some evidence of linkage at almost the same location (UCLA LOD=1.45 at 93 cM; German LOD=0.68 at 100 cM). The overlap of these two main peaks with previous findings suggests that loci linked to ADHD may lie within these regions. Meta-analysis or reanalysis of the raw data of all the available ADHD linkage scan data may help to clarify whether these represent true linked loci.