Microsporum canis pseudomycetoma and disseminated Mycobacterium genavense infection in an HIV/AIDS patient, an unusual combination

Pseudomycetomas are rare fungal subcutaneous infections caused by dermatophytes, which are mainly observed in immunocompromised patients. Mycobacterium genavense is considered an opportunistic pathogen in people living with HIV/AIDS (PLWHA), clinically resembling the presentation of Mycobacterium avium complex (MAC). Here, we describe the case of a 26-year-old PLWHA with a 3-month history of a 4cm tumoral, duroelastic and painful lesion located on the back. Histopathology of the tumoral lesion revealed chronic granulomatous inflammation with grains composed of PAS-positive and Grocott-positive septate hyphae, as well as acid-fast bacilli (AFB). Culture on Sabouraud and lactrimel agar developed colonies that were later identified as Microsporum canis. In successive samples, the AFB were identified as M. genavense by restriction analysis of PCR products. Immunocompromised PLWHA not only suffer increased susceptibility to diseases due to unusual pathogens but also atypical clinical presentation of frequently encountered pathogens.

[An emerging problem: heteroresistance in Mycobacterium tuberculosis]

Mixed infection by Mycobacterium tuberculosis (Mtb) consists in the simultaneous coexistence in the same patient of two different strains of Mtb or 2 different variants of the same strain. When one of the variants selects for resistance mutations, it is called monoclonal heteroresistance (HTR); if there are 2 different strains, one sensitive and one resistant (or with different resistance patterns), it is called polyclonal HTR. Three cases of HIV/AIDS patients are presented, all with repeated treatment adherence problems, in whom monoclonal HTR was diagnosed through Mtb complete genomic sequentiation with the coexistence of two variants of the same strain isolated from samples from lung and lymph nodes, with different resistance profiles in each case. It is important to consider the possibility of HTR, especially in patients with multiple previous therapeutic attempts and high bacillary populations, such as in advanced AIDS, since this situation potentially compromises treatment results by coexisting sensitive and resistant variants of a strain (or strains).

Five-year microevolution of a multidrug-resistant Mycobacterium tuberculosis strain within a patient with inadequate compliance to treatment

BACKGROUND

Whole-genome sequencing has shown that the Mycobacterium tuberculosis infection process can be more heterogeneous than previously thought. Compartmentalized infections, exogenous reinfections, and microevolution are manifestations of this clonal complexity. The analysis of the mechanisms causing the microevolution -the genetic variability of M. tuberculosis at short time scales- of a parental strain into clonal variants with a patient is a relevant issue that has not been yet completely addressed. To our knowledge, a whole genome sequence microevolution analysis in a single patient with inadequate adherence to treatment has not been previously reported.

CASE PRESENTATION

In this work, we applied whole genome sequencing analysis for a more in-depth analysis of the microevolution of a parental Mycobacterium tuberculosis strain into clonal variants within a patient with poor treatment compliance in Argentina. We analyzed the whole-genome sequence of 8 consecutive Mycobacterium tuberculosis isolates obtained from a patient within 57-months of intermittent therapy. Nineteen mutations (9 short-term, 10 fixed variants) emerged, most of them associated with drug resistance. The first isolate was already resistant to isoniazid, rifampicin, and streptomycin, thereafter the strain developed resistance to fluoroquinolones and pyrazinamide. Surprisingly, isolates remained susceptible to the pro-drug ethionamide after acquiring a frameshift mutation in ethA, a gene required for its activation. We also found a novel variant, (T-54G), in the 5' untranslated region of whiB7 (T-54G), a region allegedly related to kanamycin resistance. Notably, discrepancies between canonical and phage-based susceptibility testing to kanamycin were previously found for the isolate harboring this mutation. In our patient, microevolution was mainly driven by drug selective pressure. Rare short-term mutations fixed together with resistance-conferring mutations during therapy.

CONCLUSIONS

This report highlights the relevance of whole-genome sequencing analysis in the clinic for characterization of pre-XDR and MDR resistance profile, particularly in patients with incomplete and/or intermittent treatment.

Recurrences of multidrug-resistant tuberculosis: Strains involved, within-host diversity, and fine-tuned allocation of reinfections

Recurrent tuberculosis occurs due to exogenous reinfection or reactivation/persistence. We analysed 90 sequential MDR Mtb isolates obtained in Argentina from 27 patients with previously diagnosed MDR-TB that recurred in 2018 (1-10 years, 2-10 isolates per patient). Three long-term predominant strains were responsible for 63% of all MDR-TB recurrences. Most of the remaining patients were infected by strains different from each other. Reactivation/persistence of the same strain caused all but one recurrence, which was due to a reinfection with a predominant strain. One of the prevalent strains showed marked stability in the recurrences, while in another strain higher SNP-based diversity was observed. Comparisons of intra- versus inter-patient SNP distances identified two possible reinfections with closely related variants circulating in the community. Our results show a complex scenario of MDR-TB infections in settings with predominant MDR Mtb strains.

Fatty acid oxidation of alternatively activated macrophages prevents foam cell formation, but Mycobacterium tuberculosis counteracts this process via HIF-1α activation

The ability of Mycobacterium tuberculosis (Mtb) to persist inside host cells relies on metabolic adaptation, like the accumulation of lipid bodies (LBs) in the so-called foamy macrophages (FM), which are favorable to Mtb. The activation state of macrophages is tightly associated to different metabolic pathways, such as lipid metabolism, but whether differentiation towards FM differs between the macrophage activation profiles remains unclear. Here, we aimed to elucidate whether distinct macrophage activation states exposed to a tuberculosis-associated microenvironment or directly infected with Mtb can form FM. We showed that the triggering of signal transducer and activator of transcription 6 (STAT6) in interleukin (IL)-4-activated human macrophages (M(IL-4)) prevents FM formation induced by pleural effusion from patients with tuberculosis. In these cells, LBs are disrupted by lipolysis, and the released fatty acids enter the β-oxidation (FAO) pathway fueling the generation of ATP in mitochondria. Accordingly, murine alveolar macrophages, which exhibit a predominant FAO metabolism, are less prone to become FM than bone marrow derived-macrophages. Interestingly, direct infection of M(IL-4) macrophages with Mtb results in the establishment of aerobic glycolytic pathway and FM formation, which could be prevented by FAO activation or inhibition of the hypoxia-inducible factor 1-alpha (HIF-1α)-induced glycolytic pathway. In conclusion, our results demonstrate that Mtb has a remarkable capacity to induce FM formation through the rewiring of metabolic pathways in human macrophages, including the STAT6-driven alternatively activated program. This study provides key insights into macrophage metabolism and pathogen subversion strategies.

Tuberculosis is a deadly disease caused by Mycobacterium tuberculosis. Although progress has been made in tuberculosis control, there are unexplored aspects of how the immune system deals with the pathogen that need to be addressed. M. tuberculosis primarily lives in macrophages, immune cells which can destroy mycobacteria. In spite of the multiple microbicidal properties, the bacterium still manipulates the metabolism of macrophages, reflected in the accumulation lipid droplets and consequent differentiation into foamy macrophages. These lipid-laden macrophages constitute a favorable niche for the bacteria to persist hidden from our immune defense. Macrophages are classified into different programs depending on how they are activated by environmental signals, ranging from classically (microbicidal/inflammatory) to alternatively (tissue remodeling/repair/growth) activated spectrum extremes. We found that, unlike other programs, alternatively activated macrophages are reluctant to accumulate lipid droplets due to the signal transducer and activator of transcription 6 (STAT6), which promotes the degradation of those lipids. Notwithstanding, M. tuberculosis counteracts lipolysis by rewiring the metabolism of alternatively activated macrophages towards the accumulation of lipid droplets via the activation of the hypoxia-inducible factor 1-alpha (HIF-1α). Therefore, this study contributes to the better understanding of how bacillus shifts the metabolism of macrophages, which can be crucial to therapeutic purposes.

Fluoromycobacteriophages Can Detect Viable Mycobacterium tuberculosis and Determine Phenotypic Rifampicin Resistance in 3-5 Days From Sputum Collection

The World Health Organization (WHO) estimates that 40% of tuberculosis (TB) cases are not diagnosed and treated correctly. Even though there are several diagnostic tests available in the market, rapid, easy, inexpensive detection, and drug susceptibility testing (DST) of Mycobacterium tuberculosis is still of critical importance specially in low and middle-income countries with high incidence of the disease. In this work, we have developed a microscopy-based methodology using the reporter mycobacteriophage mCherry_bombϕ for detection of Mycobacterium spp. and phenotypic determination of rifampicin resistance within just days from sputum sample collection. Fluoromycobacteriophage methodology is compatible with regularly used protocols in clinical laboratories for TB diagnosis and paraformaldehyde fixation after infection reduces biohazard risks with sample analysis by fluorescence microscopy. We have also set up conditions for discrimination between M. tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM) strains by addition of p-nitrobenzoic acid (PNB) during the assay. Using clinical isolates of pre-XDR and XDR-TB strains from this study, we tested mCherry_bombΦ for extended DST and we compared the antibiotic resistance profile with those predicted by whole genome sequencing. Our results emphasize the utility of a phenotypic test for M. tuberculosis extended DST. The many attributes of mCherry_bombΦ suggests this could be a useful component of clinical microbiological laboratories for TB diagnosis and since only viable cells are detected this could be a useful tool for monitoring patient response to treatment.

Pro-inflammatory M1/Th1 type immune network and increased expression of TSG-6 in the eutopic endometrium from women with endometriosis

OBJECTIVE

The study aimed to explore the type 1 and type 2 cytokines expression in the endometrium from women affected by endometriosis compared to controls. The expression of TSG-6, a multifunctional protein involved in several inflammatory disease, was also evaluated. Study Design SETTING: Experimental clinical study.

PATIENTS

10 patients affected by endometriosis and 11 controls.

INTERVENTIONS

Patients underwent to an ultrasound transvaginal examination and a diagnostic hysteroscopy in order to exclude any uterine abnormality. All patients underwent endometrial biopsy using a Novak's curette.

MAIN OUTCOME MEASURES

The endometrial expression of type 1 (IL- 1 β TNF-α, IL-8) and type 2 (IL-10) cytokines, and of TSG-6 was evaluated by immunohistochemistry and by real time PCR. The expression of TSG-6 was confirmed by western blot.

RESULTS

Results of PCR analysis and of immunohistochemistry revealed an increased expression of IL-1β, TNF-α, IL-8 and of TSG-6 in the endometrium of endometriosic patients. IL-10 expression did not show any difference.

CONCLUSIONS

An increased expression of pro-inflammatory type 1 cytokines was demonstrated in the endometrium from endometriosic patients, suggesting an endometrial environment harmful for implantation due to the prevalence of Th1 related immunity. An increased expression of TSG-6 was also demonstrated for the first time. Our findings concur to better define the inflammatory imbalance and the abnormal endometrial receptivity, reported in literature, of the eutopic endometrium of women affected by endometriosis.

LED fluorescence microscopy in the diagnosis of tuberculosis: Fading and restaining of smears for external quality assessment

Blinded rechecking is a method proposed for external quality assurance (EQA) of auramine-stained acid-fast bacilli (AFB) smears using fluorescence microscopy (FM), however, this procedure is not well developed and slides fading over time could compromise its implementation. Since bleaching of fluorescent molecules involves temperature-dependent chemical reactions, it is likely that low temperatures could slow down this process. We stored auramine-stained slides under different environmental conditions, including -20°C, and examined them over time. The slides stored in all the environments faded. At -20°C, fading was not reduced in relation to room temperature. Restaining and re-examining smears after five months showed that the slides containing saliva and storage at -20°C were associated with failure in AFB reappearance. In conclusion, the practice of freezing slides until they are viewed should be discouraged as it has a negative effect on blinded rechecking by reducing reading concordance after restaining. Specimen quality should be considered when interpreting FM-EQA results.

Correlations between sonographically measured and actual incision site thickness of lower uterine segment after repeated caesarean section

AIM

The aim of the present study was to verify how much the sonographically measured thickness of the lower uterine segment caesarean-section (LUS-CS) scar correlates with incision site thickness in a repeated caesarean section after uterotonic administration.

METHODS

Sixty-three obstetric patients at term undergoing repeated caesarean section. LUS-CS thickness was measured sonographically before the repeated caesarean. Some seconds after delivery of the fetus and placenta and administration of an institutional, standard uterotonic, LUS was measured on the site of surgical incision (upper side and lower side) using Castroviejo's caliper. Multiple measurements were taken and averaged for improving accuracy. Mean measurements were used for calculations (unilinear correlations and multilinear regression analyses.).

RESULTS

Poor correlation was found between sonographically measured scar thickness and lower uterine side incision thickness (r 0.311; C.I. 95% 0.068-0.519; P=0.013) and between sonographically measured scar thickness and uterine scar overall incision thickness (mean of upper side and lower side measurements) (r 0.254; C.I. 95% 0.007-0.472; P=0.045). Sonographically measured scar thickness was smaller in patients with two or more previous caesareans (P=0.045) and greater in patients who had undergone the last of the previous caesarean sections longer than two years earlier (P=0.043). Patients with two or more previous caesareans had smaller upper-side incision thickness (P=0.005); smaller lower-side incision thickness (P=0.038); smaller incision site overall thickness (P=0.006).

CONCLUSION

Sonographically measured thickness and incision site thickness of the LUS-CS scar are poorly correlated (about 25%), despite the fact that patients most at risk for uterine rupture have thinner LUS, both sonographically and when measured during surgery.

The role of hysteroscopy in the diagnostic work-up of infertile asymptomatic patients

PURPOSE OF INVESTIGATION

To demonstrate that office hysteroscopy has a key-role in the diagnostic work-up of infertile couples.

MATERIALS AND METHODS

The entire database of hysteroscopies performed in 572 menstruated women from 2008 to 2011, was retrospectively analyzed. A two-dimensional correspondence analysis among endometrial patterns, age ranges, and indication for hysteroscopies was made. A main-effect hierarchical log-linear model was built to assess the goodness of the correspondences found.

RESULTS

A clear cluster of aggregation appears in case of both primary and secondary infertility, with and without other indications for hysteroscopy, as well as in case of primary infertility with irregular menstrual bleeding. In such patients, chronic endometritis, normal pattern, and uterine malformations were frequently found. The most significant correspondence was found for normal pattern and chronic endometritis in case of secondary infertility and primary infertility, respectively.

CONCLUSIONS

Office hysteroscopy should be reconsidered in the diagnostic work-up of infertile couples. It is able to assess or rule out endometrial factor for female infertility.

Primitive omental leiomyoma: a case report

Primitive omental leiomyomas are very rare. The primitive omental location of the leiomyoma is quite difficult to determine, with the possible presence of "parasite" myomas and of omental metastasizing myomas. Moreover, omental masses may be primitive or secondary metastasis from neoplasms. In this case report a primitive omental leiomyoma is described, and their diagnosis and management are briefly discussed, in order to improve the knowledge of this very uncommon disease.

Asymptomatic large bladder diverticulum

The authors report a case of a 61-year-old woman diagnosed with large bladder diverticulum. Diagnosis was performed only after a series of investigations carried out for the occasional finding of hypercreatininaemia. Although the significant volumes of post void residual (PVR) and the relevant urine stagnation in the diverticulum, subjective symptomatology was absent and urinalysis and urine culture were negative. The scheduled therapeutic plan consisted of fosfomycin three grams every ten days for sixmonths, self-catheterization twice a day, voiding on a time schedule, and adequate fluid intake. The monthly scheduled follow-up at one year showed good general health, good compliance with the therapy, no urinary tract infections, a decrease in creatininemia to 1.2 mg/dl, and regression of nephrohydrosis to a mild stage. In conclusion, the absence of symptoms and negative urinalysis or urine culture allows expectant management despite the considerable size of the bladder diverticulum.

Effectiveness of vaginal adelmidrol for treating pelvic visceral discomforts and anxiety: a prospective observational study

AIM

The aim of this paper was to show that self-assessed anxiety in patients with pelvic visceral discomforts is reduced after the intravaginal administration of adelmidrol.

MATERIAL AND METHODS

Twenty-four patients who described themselves as anxious (scoring 5 or more in a 1 to 10 scale in a self-assessment test) and who suffered from pelvic visceral discomfort (during defecation, urination, sexual intercourse and menstruation) were enrolled in the study. Pelvic visceral discomforts were assessed using a questionnaire in which patients were asked to assign a score between 1 and 10 according to intensity. The patients were offered intravaginal adelmidrol therapy (2%, 4.5 mL twice a day for 30 days). The patients were interviewed again and asked to self-assess anxiety and pelvic visceral discomfort at the end of therapy.

RESULTS

12 patients underwent adelmidrol therapy. With the exception of urinary discomfort, all the median scores of pelvic visceral discomforts had improved after 30 days, with significant values achieved for menstruation (P=0.013) and sexual intercourse (P=0.013). Anxiety had also decreased after 30 days (P=0.025), regardless of changes in discomfort levels.

CONCLUSION

Adelmidrol could selectively modulate the visceral nociceptive pathways (interoception), relieving pelvic discomfort. This action should have an independent effect on anxiety responses.

Nonhormonal management of postmenopausal women: effects of a red clover based isoflavones supplementation on climacteric syndrome and cardiovascular risk serum profile

PURPOSE OF INVESTIGATION

The aim of this prospective randomized study was to evaluate a red clover based isoflavones supplementation in the treatment of climacteric syndrome and its effects on cardiovascular risk serum profile.

MATERIALS AND METHODS

The study included 150 healthy postmenopausal women that were randomly assigned to receive phytoestrogens tablets, amounting in a total daily intake of 60.8 mg red clover isoflavones plus 19.2 mg soy isoflavones (n = 75), or placebo (n = 75). The authors evaluated teh following: daily number of hot flushes and Kupperman Index at baseline and after one and three months; serum total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, prothrombin time (PT), partial thromboplastin time (PTT), fibrinogen, and antithrombin III (ATIII) at baseline and after three and six months.

RESULTS

One hundred twenty-eight patients completed the study: 67 in the active group and 61 in the placebo group. The treatment led to a progressive significant reduction (p < 0.05) of the number of hot flushes in the active group compared to placebo already after one month, while Kupperman Index was statistically reduced after three months. No significant variation in total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, PT, PTT, fibrinogen, and ATIII were found.

CONCLUSION

The present findings suggest that a red clover based isoflavones supplementation in healthy postmenopausal women is promptly effective on climacteric syndrome, improves neurovegetative symptoms, safe on cardiovascular risk serum profile, and does not modify lipids and coagulation.

The pathogenesis of endometrial polyps: a systematic semi-quantitative review

The pathogenesis and natural history of endometrial polyps are not very clear. The objective of this study was to assess the opinions of international medical literature regarding the factors involved in the pathogenesis of endometrial polyps and to organize the results consistently with what is known about endometrial physiology.

MATERIALS AND METHODS

A systematic review was carried out with the following search engines: PubMed, OVID, Scopus, SCIELO, and AJOL. Two hundreds forty-six abstracts were selected from the literature; of these abstracts, 58 factors were extracted and set as causative, non-causative, unclear or protective link with endometrial polyps. This relation is described through a correspondence analysis and tested with a main effect hierarchical log-linear model.

RESULTS

The log-linear model resulted significant for the correspondence found with the following factors: (i) causative link (ageing, bcl-2 protein, excess weight/obesity, tamoxifen regardless of timing, relationship between estrogen receptors and prog-estinics, unbalanced estrogen therapy, estrogen-like effect, and unbalance between estrogens and progestinics), (ii) protective link (progestinics, antiestrogenic action), (iii) unclear link (menopause, ki-67 protein, angiogenesis, tamoxifen for a short time, tamoxifen for a long time, hormone replacement therapy (HRT), endometritis/inflammation), and (iv) non-causative link (none of the factors specifically).

DISCUSSION

Subsequently to a review of the physiology of the endometrium, the onsetting of endometrial polyps was suggested through estrogen-related and non-estrogen related ways; the two ways can overlap. The most implied factors in the development of endometrial polyps are linked with one of these or both ways.

Five years (2004-2009) of a restrictive law-regulating ART in Italy significantly reduced delivery rate: analysis of 10,706 cycles

STUDY QUESTION

Was the delivery rate of ART cycles negatively affected by the enactment of the Law 40/2004 by the Italian Parliament which imposed a long list of restrictions for ART procedures?

SUMMARY ANSWER

This large and extensive comparative analysis of ART outcomes prior to and after the introduction of the Law 40 revealed a significant reduction in pregnancy and delivery rates per cycle, independent of age or other clinical variables, once the law went into effect.

WHAT IS KNOWN ALREADY

Several studies have been published on the effect of Law 40/2004 on ART outcomes, some authors demonstrating a negative impact of the Law in relation to specific etiologies of infertility, other authors showing opposite conclusions.

STUDY DESIGN, SIZE, DURATION

Retrospective clinical study of 3808 patients treated prior to the enactment of the Law, September 1996-March 2004 (Group I) and 6898 treated during the Law, March 2004-May 2009 (Group II).

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 10 706 ART cycles were analysed, 3808 performed before and 6898 after the application of the Law. An intention-to-treat statistical analysis was performed to detect pregnancy and delivery rates (pregnancies ≥ 24 weeks) per started cycle. A P value of <0.05 was considered statistically significant. We analysed different outcomes: differences in fertilization, pregnancy and delivery rate, multiple pregnancies and miscarriage rates between the two time periods.

MAIN RESULTS AND THE ROLE OF CHANCE

The delivery rate for started cycle was 20% before and 16.0% after the introduction of the Law representing a 25% reduction (P < 0.001). The multivariate analysis, corrected by female age of >38 years, duration of infertility, basal FSH level and number of retrieved oocytes, showed a 16% lower delivery rate (odds ratio: 0.84; confidence interval: 0.75-0.94). This statistical approach removed the risk that the observed effects were due to chance and confirmed unequivocally that the Law was an independent factor responsible for the reduced likelihood of a successful outcome.

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective study. A prospective randomized study, with patients treated in the same time period and randomized to restrictions or not, would have minimized potential limitations due to differences in years of treatments.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings based on the analysis of such a large number of cycles proved clearly and unequivocally that imposing restrictions on the practice of ART penalized patients. These data represent a relevant clinical contribution for countries still debating the enactment of restrictive limitations of ART.

Malignant mixed müllerian tumor of the fallopian tube coincident with a primary serous carcinoma of the ovary. Case report

Malignant mixed müllerian tumors are very rare neoplasms of the fallopian tube, and treatment is not well defined. A case of malignant mixed müllerian tumor of the tube concomitant with a primary serous carcinoma of the ovary is reported. It was unclear if there were two distinct neoplasms in the same patient, or if it was a single tumor with a sarcomatous fallopian conversion of the serous component, as described for some recurrent ovarian carcinomas. Chemotherapy for ovarian carcinoma with intraperitoneal metastasis was performed, with about a three-year interval-free period of disease, as could be expected for ovarian carcinomas at the same stage. Such coexistence of these two tumors does not afford adequate staging of the malignancy. Therapy for the very rare cases similar to the one reported here needs to be improved.

Influence of human menopausal gonadotrophin treatment on testicular blood flow and on seminal plasma nitric oxide levels in infertile males

Gonadotrophin treatment is capable of increasing intratesticular blood flow and improving sperm fertilization potential. A nitric oxide (NO)-mediated mechanism may play a role. This study aimed at evaluating whether the increase in intratesticular blood flow, in response to human menopausal gonadotrophin (hMG) treatment, is accompanied by an increase in seminal plasma NO levels in 20 normogonadotropic males affected by severe oligoasthenoteratozoospermia. Patients received 150 IU of hMG, three times a week for 3 months. Before starting treatment and at month 3 of therapy, levels of NO in the seminal plasma were determined, followed by ultrasound scanning of testis, Doppler evaluation of intratesticular vascular resistance, serum hormone and conventional semen evaluation. Statistical analysis was performed by using Wilcoxon test; the limit of statistical significance was p<0.05. At the end of treatment, seminal plasma concentration of NO, conventional semen parameters and testicular volume did not increase significantly. Follicle-stimulating hormone serum level significantly increased (p=0.014) after treatment, whereas luteinizing hormone, testosterone and oestradiol values did not change. The resistance index of both intratesticular arteries significantly decreased (p=0.012 and 0.005 for right and left testes respectively). The results of this study confirmed the positive effect of exogenous hMG on testicular blood flow, but failed to demonstrate any effect of hMG treatment on NO levels in the seminal plasma in infertile males.

Molecular characterization of methicillin-resistant Staphylococcus aureus isolates reveals the spreading of a new clone in Buenos Aires City

We performed a hospital-acquired methicillin-resistant Staphylococcus aureus molecular study in Buenos Aires city. Four clones were found harboring the transposable elements Tn4001 and Tn5405 and the erythromycin resistance determinants ermA and mef(E). Of the isolates, 73% belonged to a clone found previously in the city of Córdoba, which showed an epidemic behavior initially attributed to the widely disseminated South American clone.

Tn7 distribution in Helicobacter pylori: a selective paradox

The presence of class 1, 2 and 3 integrons in Helicobacter pylori, which in other species are usually related to antimicrobial resistance, were looked for in 40 epidemiologically-unrelated isolates. The presence of the class 2 integrase, which led to the discovery of Tn7, was found in 15 of 35 different clones identified by lspA-glmM polymorphism. MIC values for trimethoprim and streptomycin were not affected by the presence or absence of dfrA1 and aadA1 genes. The polyclonal spread of Tn7 showed the ability of H. pylori to harbour antimicrobial resistance mechanisms, usually located on plasmids, and also suggested that other important mechanisms of resistance may also be acquired, which would result in failure of chemotherapy.

Helicobacter pylori vacA genotypes, cagA status and ureA-B polymorphism in isolates recovered from an Argentine population

Several reports have evidenced geographic differences in the prevalence of vacA (vacuolating cytotoxin gene) alleles and cagA (cytotoxin-associated gene) status among Helicobacter pylori isolates. We investigated the occurrence of these virulence-associated genes status among our isolates, and their relationship with ulcer disease outcome. Besides, ureA-B polymorphism was studied. One hundred isolates, comprising 32 from patients with ulcer disease (UD) and 68 from patients with non-ulcer dyspepsia (NUD), were analyzed. Eighty-four percent of isolates were cagA-positive without statistically significant difference in prevalence between patients with UD or NUD. Genotype vacA-s1m1 was predominant, although unlike other South American regions, subtype s1am1 occurrence was higher than s1b. The multivariate model used to estimate the predictive value of cagA and vacA status for UD development disclosed infection with vacA-s1am1 isolates as the only variable that increased the risk of UD onset. ureAB fingerprinting showed considerable genetic divergence among isolates, however, confirmed that certain DNA banding profiles are conserved worldwide.

Tolerability of the mini-pan-endoscopic approach (transvaginal hydrolaparoscopy and minihysteroscopy) versus hysterosalpingography in an outpatient infertility investigation

OBJECTIVE

To compare the acceptance and tolerability of the mini-pan-endoscopic approach (transvaginal hydrolaparoscopy [THL] combined with minihysteroscopy) versus hysterosalpingography (HSG) for evaluating tubal patency and the uterine cavity in an outpatient infertility investigation.

DESIGN

Randomized controlled study.

SETTING

University hospital.

PATIENT(S)

Twenty-three infertile patients without obvious pelvic pathology.

INTERVENTION(S)

Women were randomly divided into two groups. One group underwent minihysteroscopy and THL with tube chromoperturbation as first investigation and HSG within the following 7 days, while in the other group the investigation sequence was inverted. Women reported pain experienced before and at the end of procedures.

MAIN OUTCOME MEASURE(S)

Mean duration of procedures, level of pain experienced, diagnostic agreement about tubal patency and uterine cavity normality.

RESULT(S)

THL and minihysteroscopy took significantly more time but was significantly less painful than HSG. Regarding tubal patency, in 95.5% of cases THL agreed with HSG. In one case, HSG diagnosed a bilateral obstruction of tubes, whereas at THL a bilateral spreading of methylene blue was seen. Agreement on intrauterine pathologies between minihysteroscopy and HSG was poor (43%); the number of intrauterine abnormalities found at hysteroscopy was significantly greater than at HSG.

CONCLUSION(S)

THL in association with minihysteroscopy provided more information and was better tolerated than HSG in an outpatient infertility investigation.

The pleiotropic phenotype of tomato cells selected for altered response to Fusarium oxysporium f. sp. lycopersici cell wall components

With the aim of better understanding in vitro host-parasite interactions, tomato cell lines selected for altered response to Fusarium oxysporum f. sp. lycopersici cell wall components were further characterized. Particularly, their behaviour in dual culture in regard to both fungal inhibition and peroxidase activation was analysed and selected, and control cell clones were screened for esopolysaccharide content and toxin tolerance. Interclonal differences in growth response to 2,4-D and DMSO and the capacity to grow on a medium devoid of hormones (habituation) were taken as parameters representative of physiological variability not directly correlated with the response to pathogens. Significant differences between clones selected for increased (F+) and decreased (F-) response to fungal elicitors were found for pathogen inhibition, peroxidase and esopolysaccharide content, toxin tolerance being reduced in F but not significantly different from the control in F+. As expected, clonal variability for the response to 2,4-D and DMSO, although significant, was not connected with hostparasite interactions. The data reported thus show that selection for a character (response to elicitors), probably critical for the response to pathogens, may lead to the recovery of genotypes showing a set of modifications suggestive of a cascade of events leading to active defense.

Polypeptide 2A of human rhinovirus type 2: identification as a protease and characterization by mutational analysis

Evidence is presented that the protein 2A of human rhinovirus serotype 2 (HRV2) is a protease. On expression of the VP1-2A region of HRV2 in bacteria, protein 2A was capable of acting on its own N-terminus; derived extracts specifically cleaved a 16 amino acid oligopeptide corresponding to the sequence at the cleavage site. Cleavage of the oligopeptide substrate provides a convenient in vitro assay system. Deletion experiments showed that removal of 10 amino acids from the carboxy terminus inactivated the enzyme. Site-directed mutagenesis identified an essential arginine close to the C-terminus and showed that the enzyme was sensitive to changes in the putative active site. This analysis supports the hypothesis that 2A belongs to the group of sulfhydryl proteases, although sequence comparisons indicate that the putative active site of HRV2 2A is closely related to that of the serine proteases.