Flutamide-metformin plus an oral contraceptive (OC) for young women with polycystic ovary syndrome: switch from third- to fourth-generation OC reduces body adiposity

BACKGROUND: Low-dose flutamide-metformin has been developed as a background therapy for non-obese adolescents and young women with hyperinsulinaemic hyperandrogenism, a variant of polycystic ovary syndrome (PCOS). We verified whether the lipolytic efficacy of flutamide-metformin in women with PCOS is enhanced by giving an oral contraceptive (OC) co-therapy that contains drospirenone, instead of gestodene, as progestin. METHODS: An open-labelled study was carried out in which non-obese women with PCOS (n = 29; age approximately 20 years), who had been on a combination of flutamide (62.5 mg/day), metformin (850 mg/day) and ethinylestradiol-gestodene for 8-15 months, were randomized for replacement of the gestodene OC by a drospirenone OC. Assessments of endocrine-metabolic state and body composition (by dual-energy X-ray absorptiometry) were performed at randomization and after 6 months. RESULTS: The switch to drospirenone OC was accompanied by a reduction of total and abdominal fat (mean -0.8 and -0.5 kg) and by an increment of lean body mass (+0.6 kg; all P < 0.01), so that body adiposity was strikingly reduced without changing body weight. CONCLUSION: In non-obese women with PCOS, low-dose flutamide-metformin reduces total and abdominal fat excess more effectively if contraceptive co-therapy contains drospirenone, instead of gestodene, as progestin.     

Plant perception systems for pathogen recognition and defence

Recognition of and defence against microbial infections are universal adaptations of multicellular organisms. Plants express a sophisticated molecular system for recognition of and response to potentially pathogenic microorganism. Although the environments of plant and animal cells are vastly different and present unique challenges to invading pathogens, the molecular basis of the innate immune response shows remarkable evolutionary conservation in both kingdoms. Even if more cellular components are continually being identified in plants, the mechanism, interactions and responses are only partly understood. Furthermore, most of this research has been performed in the model plant Arabidopsis thaliana and a significant effort will be needed to understand the above processes in crop species and in natural populations. In this review I will describe examples of the best characterized recognition systems in plants, that mediate pathogen perception either through the perception of highly variable and non-essential pathogen molecules or via conserved microbial structures called pathogen associated molecular patterns (PAMPs).     

Humoral immunity patterns based on antibody reactivity to rotavirus antigens in Brazilian children under 5 years of age

The age distribution of antibody to simian rotavirus (SA-11) was studied in serum specimens obtained from 399 children aged to 5 years and living in the city of Recife (PE), located in the north eastern region of Brazil. Sera were examined for group-specific rotavirus antibody using a blocking enzyme immunoassay (bELISA) and a hemagglutination inhibition antibody (HIA) test, and for anti-VP2, anti-VP4, anti-VP6, and anti-VP7 antibodies using an immunoblotting assay (IBA). Antibody prevalence was similar in all bELISA and HIA assays, showing a steep rise in the 6- to 17-month-old age groups. The results indicate early acquisition of antibody to rotavirus. The majority of children aged 2 to 4 years had bELISA (50% to 60%) and HIA (70% to 81%) antibodies. There was an association in prevalence data obtained by HIA and bELISA with immunoblotting (IBA), revealing four serologic profiles. Children with profiles I and II (60%) respectively had HAI and ELISA antibody or HAI antibody alone and all had immunoprotective antibodies to VP4 and/or VP7. These children were regarded as “immune,” resembling convalescent patients with a rotavirus infection. Children with profile III (4%) had no HIA antibody and only non-protective anti-VP6 and/or VP7 antibody, and were considered to be “partially immune.” Children with profile IV (36%) had no detectable antibody and were classified as “nonimmune.” These children should be considered to be susceptible to rotavirus infection, with the risk of developing clinically severe diarrhea. © 1996 Wiley-Liss, Inc.     

Ecology of hantaviruses in Mexico: Genetic identification of rodent host species and spillover infection

In our recent epidemiological survey conducted in Mexico for hantavirus infection, we identified three distinct viruses circulating in Mexican wild rodents, namely Montano virus (MTNV), Huitzilac virus (HUIV), and Carrizal virus (CARV). To gain a detailed understanding of hantavirus epidemiology and its associated hosts, 410 rodents were captured at eight collecting points in Morelos and Guerrero, Mexico, and examined for hantavirus seroprevalence, the presence of viral RNA, and rodent host species identification using cytochrome b gene sequences. Of the 32 species captured, seven species were positive for hantavirus: Peromyscus beatae (31/127; 24.4%), Reithrodontomys sumichrasti (6/15; 40%), Reithrodontomys megalotis (2/25; 8%), Peromyscus aztecus evides (1/1; 100%), Peromyscus megalops (1/41; 2.4%), Megadontomys thomasi (1/9; 11.1%), and Neotoma picta (1/6; 16.7%), with an overall prevalence of 10.5%; virus genome persisted in the majority of seropositive rodents. Nucleotide sequence and phylogenetic analysis showed that the viruses belonged mainly to the three lineages previously identified. The data showed that MTNV and CARV were primarily carried by P. beatae and R. sumichrasti, respectively. In addition, the data revealed an apparent complex interaction between hantaviruses and their hosts, suggesting active transmission and/or spillover infections within sympatric rodent species.     

The N-terminus of the Montano virus nucleocapsid protein possesses broadly cross-reactive conformation-dependent epitopes conserved in rodent-borne hantaviruses

The hantavirus nucleocapsid (N) protein is an important immunogen that stimulates a strong and cross-reactive immune response in humans and rodents. A large proportion of the response to N protein has been found to target its N-terminus. However, the exact nature of this bias towards the N-terminus is not yet fully understood. We characterized six monoclonal antibodies (mAbs) against the N protein of Montano virus (MTNV), a Mexican hantavirus. Five of these mAbs recognized eight American hantaviruses and six European and Asian hantaviruses, but not the Soricomorpha-borne Thottapalayam hantavirus. The N protein-reactive binding regions of the five mAbs were mapped to discontinuous epitopes within the N-terminal 13-51 amino acid residues, while a single serotype-specific mAb was mapped to residues 1-25 and 49-75. Our findings suggest that discontinuous epitopes at the N-terminus are conserved, at least in rodent-borne hantaviruses, and that they contribute considerably to N protein cross-reactivity.     

Major histocompatibility complex and strong human leukocyte antigen-DRB1 and gender association with Vogt-Koyanagi-Harada syndrome in Mexican Mestizos

Vogt-Koyanagi-Harada syndrome (VKH) is a multisystem autoimmune disorder mediated by cytotoxic T cells targeting melanocytes antigen(s). A strong major histocompatibility complex (MHC) association with HLA-DRB1*04:05 has been demonstrated in different populations. We investigated the contribution of HLA-A*, -B*, -C*, -DRB1*, and -DQB1* genes, belonging to the human leukocyte antigen (HLA), to the expression of VKH and we analyzed the influence of gender on the HLA association. A total of 76 patients and 256 healthy Mexican Mestizo individuals were included. HLA-A, B, C, and DQB1 typing was performed using the polymerase chain reaction, and hybridization was done using sequence specific probes. DRB1 alleles were defined by means of sequence base typing. The frequency of DRB1*04:05 (odds ratio=2.95) and DRB1*04:04 (odds ratio=2.79) were found to be significantly increased in the patients, conferring a similar risk. Gender stratification analysis showed that these alleles were associated with female gender only. No HLA class I or class II alleles were significantly deviated in males. The frequency of DRB1*04:07 was increased in the whole group, upon withdrawal from analysis the DRB1*04:04 and *04:05 positive patients. A trend of DRB1 alleles contributing to the expression of VKH is suggested: DRB1*04:05=*04:04>*04:07>*01:01>*01:02. Although none of the results were significant after the p value was corrected, the data are consistent with those in numerous other studies, suggesting that several different DRB1* alleles may be involved in the etiopathogenesis of the disease by presenting an overlapping set of ocular peptides to the T cells, which in turn may trigger the autoimmune response that is present in the patients.     

Endoscopic bile duct brushing of malignant pancreatic biliary strictures: retrospective study with comparison of conventional smear and ThinPrep techniques

Endoscopic bile duct brushing (EBDB) is carried out to differentiate benign from malignant biliary strictures in patients who have pancreaticobiliary disease. The sensitivity of this method for the diagnosis of malignancy is relatively low. The aim of this study is to analyze the cytomorphologic features that are helpful in increasing the sensitivity of detecting these lesions on cytologic samples. These features are compared with slides prepared with the ThinPrep technique. The study included 142 patients with bile duct obstruction or pancreatic mass who underwent EBDB and follow-up surgery or biopsy between 1997 to 2000. Twenty-five (18%) of these cases were positive for malignancy in both EBDB and follow-up surgical biopsy; 20 of these cases were used as positive controls (PC). Sixty-one (43%) were negative in both EBDB and follow-up surgical biopsy specimens, and 21 of those cases were used as negative controls (NC). Fifty-six (39%) cases were negative/atypical in EBDB cytology but were suspicious or positive in the surgical or biopsy specimens (false-negative). We identified the cytologic criteria that were helpful in differentiating our positive and negative control groups and applied these criteria to our false-negative group to see whether our sensitivity could be increased, using well-defined cytologic criteria alone. Of the 56 false-negative cases, 9 (16%) were upgraded to suspicious/positive based on the presence of the following features: three-dimensional (3D) micropapillae (95% PC vs 19% NC, P < 0.0001), anisonucleosis (90% PC vs 5% NC, P < 0.0001), high nuclear-to-cytoplasmic (N/C) ratio (95% PC vs 9% NC, P < 0.0001), nuclear contour irregularity (65% PC vs 24% NC, P = 0.0079), and prominent nucleoli (70% PC vs 38% NC, P = 0.0406). Cytomorphologic features which were not helpful in distinguishing positive and negative cases were: single naked nuclei (50% PC vs 28% NC, P = 0.1597), chromatin granularity (50% PC vs 62% NC, P = 0.54), and necrosis (10% PC vs 5% NC, P = 0.5197). Improvement in diagnostic sensitivity for carcinoma of pancreaticobiliary tract in EBDB samples may be achieved by identifying the key malignant cytomorphologic features: 3D micropapillae, anisonucleosis, nuclear contour irregularity, prominent nucleoli, and high N/C ratio. The sensitivity in detecting malignant biliary strictures increased from 31% to 42% based on these criteria in our current study.     

The HLA-G 14-base pair deletion allele and the deletion/deletion genotype are associated with persistent HBe antigenemia in chronic hepatis B infection

Background and aims: HLA-G has well-recognized immunomodulatory properties, and this molecule is frequently expressed in the livers of hepatitis B virus (HBV)-infected patients. Because the HLA-G 14 bp-insertion/deletion polymorphism (rs371194629) has been associated with the magnitude of HLA-G expression, we evaluated this polymorphism in the recognized evolutionary forms of chronic HBV infection. Methods: We studied 196 chronic HBV-infected patients (118 HBeAg-negative chronic hepatitis, 53 HBeAg-positive chronic hepatitis and 25 inactive carriers exhibiting low levels of serum HBVDNA and persistently normal ALT levels), and 202 healthy individuals. Chronic hepatitis HLA-G typing was performed using PCR-amplified DNA hybridized with specific primers. Results: The frequencies of the insertion/deletion alleles and genotypes were very similar in patients and controls. After patient stratification according to the evolutionary form of the chronic HBV infection, the frequencies of the deletion allele (P = 0.0460; OR = 1.26; 95%CI = 1.01–1.45) and of the deletion/deletion genotype (P = 0.0356; OR = 2.08; 95%CI = 1.05–4.09) were overrepresented in HBeAg-positive patients when compared to HBeAg-negative patients. No differences were observed when HBV inactive carriers were compared to HBeAg-negative chronic hepatitis patients. Conclusions: Because the 14-bp deletion allele has been associated with increased HLA-G production and because HLA-G may down regulate the cytotoxic activity of TCD8 and NK cells, patients exhibiting the 14-bp deletion allele at single or double doses are at increased risk for developing chronic forms of HBV associated with persistent viremia and worse prognoses.     

Imaging Trypanosoma cruzi within tissues from chagasic patients using confocal microscopy with monoclonal antibodies

Confocal fluorescence microscopy combined with differential interference contrast imaging of tissues from chagasic patients enabled the unequivocal identification of the parasite Trypanosoma cruzi. Using different monoclonal antibodies that indicate the parasite form and replication stage in conjunction with DNA labelling, specimens derived from distinct clinical forms of the disease were examined. Intracellular amastigote forms of the parasite were clearly detected in heart, brain, skin, lung, and kidney. Dividing amastigotes as well as trypomastigote forms were recognized in samples obtained from patients undergoing either acute-phase or some form of reactivation caused by immunosuppression. Received: 22 December 1998 / Accepted: 11 March 1999     

Gain of multiple copies of the CBFB gene: a new genetic aberration in a case of granulocytic sarcoma

Granulocytic sarcomas (GS) are tumor masses of immature myeloid cells presenting at an extramedullary site, mainly the skin, bone, and lymph node. They are often associated with acute myeloid leukemia (AML) with monoblastic or myelomonocytic differentiation, including either AML M2 with t(8;21)(q22;q22) or AML M4Eo with inv(16)(p13q22). We present a case diagnosed with GS associated with AML M4 that presented a normal karyotype with conventional cytogenetic analysis. Although the myeloblasts did not show the inv(16)(p13q22) (CBFB/MYH11), a gain of multiple copies of the CBFB gene was detected with fluorescence in situ hybridization analysis. To our knowledge, no cases with this rare genetic anomaly have been previously described.