Genomic imbalances in esophageal carcinoma cell lines involve Wnt pathway genes

AIM:To identify molecular markers shared across South African esophageal squamous cell carcinoma(ESCC) cell lines using cytogenetics,fluorescence in situ hybridization(FISH) and single nucleotide polymorphism(SNP) array copy number analysis.METHODS:We used conventional cytogenetics,FISH,and multicolor FISH to characterize the chromosomal rearrangements of five ESCC cell lines established in South Africa.The whole genome copy number profile was established from 250K SNP arrays,and data was analyzed with the CNAT 4.0 and GISTIC software.RESULTS:We detected common translocation breakpoints involving chromosomes 1p11-12 and 3p11.2,the latter correlated with the deletion,or interruption of the EPHA3 gene.The most significant amplifica-tions involved the following chromosomal regions and genes:11q13.3(CCND1,FGF3,FGF4,FGF19,MYEOV),8q24.21(C-MYC,FAM84B),11q22.1-q22.3(BIRC2,BIRC3),5p15.2(CTNND2),3q11.2-q12.2(MINA) and 18p11.32(TYMS,YES1).The significant deletions included 1p31.2-p31.1(CTH,GADD45α,DIRAS3),2q22.1(LRP1B),3p12.1-p14.2(FHIT),4q22.1-q32.1(CASP6,SMAD1),8p23.2-q11.1(BNIP3L) and 18q21.1-q21.2(SMAD4,DCC).The 3p11.2 translocation breakpoint was shared across four cell lines,supporting a role for genes involved at this site,in particular,the EPHA3 gene which has previously been reported to be deleted in ESCC.CONCLUSION:The finding that a significant number of genes that were amplified(FGF3,FGF4,FGF19,CCND1 and C-MYC) or deleted(SFRP2 gene) are involved in the Wnt and fibroblast growth factor signaling pathways,suggests that these pathways may be activated in these cell lines.

Microscopic colitis as a missed cause of chronic diarrhea

AIM: To determine the prevalence of increased intraepithelial lymphocytes, using immunohistochemistry in patients with normal colonoscopy and near normal biopsy. METHODS: We retrospectively reviewed all non-malignant colon mucosal biopsies between 2005 and 2007, reported as normal, chronic inflammation or melanosis coli in patients who were undergoing routine colonoscopy. Immunohistochemistry using CD3 was performed on all mucosal biopsies and an intraepithelial lymphocyte count (IEL) was determined. Cases with an IEL count of ≥ 20 IELs per 100 surface epithelial cells were correlated with demographic, clinical and follow-up data. A further subgroup was evaluated for lymphocytic colitis.RESULTS: Twenty (8.3%) of 241 cases revealed an IEL count ≥ 20. Six (2.5%) patients were identified as having lymphocytic colitis (P < 0.001), of whom, five were missed on initial evaluation (P = 0.01). Four of these five patients were labeled with diarrhea-predominant irritable bowel syndrome (IBS). On follow-up, three of the remaining 20 cases were diagnosed with malignancy (renal cell carcinoma and myelodysplastic syndrome) and one had an unknown primary tumor with multiple liver metastases. Two cases of collagenous colitis with an IEL count < 10 were included in this study. Increased IELs were not confined to patients with diarrhea as a primary presenting symptom, but were also present in patients with abdominal pain (n = 7), constipation (n = 3) and loss of weight (n = 1). CONCLUSION: Immunohistochemistry using CD3 is of value in identifying and quantifying IELs for the presence of microscopic colitis in patients with diarrheapredominant IBS.

Primary esophageal sclerosing mucoepidermoid carcinoma with “tissue eosinophilia”

Mucoepidermoid carcinoma(MEC)is a rare primary esophageal malignancy.It is characterized by poor clinical recognition,pre-operative diagnostic challenges and a lack of standardized therapeutic guidelines.We report the clinicopathological features of a hitherto unreported variant of esophageal MEC,sclerosing MEC with"tissue eosinophilia",in a mid-esophageal location in a 51-year-old female.The diagnosis of the initial biopsy was challenging,because of the small size,poor orientation and inadequate representation of the MEC components.Recognition of the resectability of the tumor prompted surgical resection and enabled a demonstration of the low grade foci containing intermediate cells,mucin pools and the hitherto undescribed presence of stromal sclerosis and tissue eosinophils in esophageal MEC.Heightened clinicopathological awareness of esophageal MEC facilitated a definitive diagnosis and patient management.Increased recognition andglobal documentation of esophageal sclerosing MEC with"tissue eosinophilia"is necessary to improve the understanding and diagnosis of this malignancy in this location and to improve management guidelines.

Histopathological profile of gastritis in adult patients seen at a referral hospital in Kenya

AIM: To conduct a detailed histological study of gastritis in adult patients attending an endoscopy clinic at a Kenyan teaching and referral hospital. METHODS: Biopsy specimens from consecutive patients were examined and graded according to the Updated Sydney System for H pylori infection, chronic inflammation, neutrophil activity, glandular atrophy and intestinal metaplasia. Also documented were gastric tissue eosinophil counts and presence of lymphoid follicles. RESULTS: The rate of the graded variables, in the antrum and corpus respectively, were as follows: H pylori infection (91%, 86%), chronic inflammation (98%, 93%), neutrophil activity (91%, 86%), glandular atrophy (57%, 15%) and intestinal metaplasia (11%, 2%). Lymphoid follicles were noted in 11% of cases. Duodenal and gastric ulcers were documented in 32% and 2% respectively. The mean eosinophil count was 5.9 ± 0.74 eosinophils/ HPF and 9.58 ± 0.93 eosinophils/HPF in the corpus and antrum respectively. Significant association was found between the degree of H pylori colonisation with chronic inflammation, neutrophil activity and antral glandular atrophy. Biopsies from the antrum and corpus showed significant histopathological discordance for all the graded variables. H pylori negative cases were associated with recent antibiotic use. CONCLUSION: The study reaffirms that H pylori is the chief cause of gastritis in this environment. The majority of patients show a moderate to high degree of inflammation but a low degree of glandular atrophyand intestinal metaplasia. The study shows that inter- relationships between the histological variables in this African population are similar to those found in other populations worldwide including non-African populations.

African origins and chronic kidney disease susceptibility in the human immunodeficiency virus era

Chronic kidney disease(CKD) is a major public health problem worldwide with the estimated incidence growing by approximately 6% annually. There are striking ethnic differences in the prevalence of CKD such that, in the United States, African Americans have the highest prevalence of CKD, four times the incidence of end stage renal disease when compared to Americans of European ancestry suggestive of genetic predisposition. Diabetes mel itus, hypertension and human immunodeficiency virus(HIV) infection are the major causes of CKD. HIV-associated nephropathy(HIVAN) is an irreversible form of CKD with considerable morbidity and mortality and is present predominantly in people of African ancestry. The APOL1 G1 and G2 alleles were more strongly associated with the risk for CKD than the previously examined MYH9 E1 risk haplotype in individuals of African ancestry. A strong association was reported in HIVAN, suggesting that 50% of African Americans with two APOL1 risk alleles, if untreated, would develop HIVAN. However these two variants are not enough to cause disease. The prevailing belief is that modifying factors or second hits(including genetic hits) underlie the pathogenesis of kidney disease. This work reviews the history of genetic susceptibility of CKD and outlines current theories regarding the role for APOL1 in CKD in the HIV era.

Emerging Carbapenem-Resistant <i>Enterobacter cloacae</i>Producing OXA-48-, VIM- and IMP-Type-<i>β</i>-Lactamases in Eastern Cape Hospitals in South Africa

Introduction: Enterobacter cloacae strains have been isolated from Eastern Cape hospitalised patients. Methodology: We have molecularly characterised blaOXA-48-, blaIMP- and blaVIM-expressing E. cloacae isolates demonstrating resistance to carbapenems from five hospitals by multilocus sequence typing. Organism identification and antimicrobial susceptibility testing was done using automated systems and the isolates were screened for carbapenemases using either conventional or real-time PCR and then typed using multilocus sequence typing. Further characterisation of IMP-type-producing E. cloacae isolates, an unusual occurrence in South Africa, was performed by pulsed-field gel electrophoresis. Results and Conclusion: Twenty-five E. cloacae isolates from 24 patients were investigated. Eighteen (72%) isolates harboured either one of the following genes: blaIMP, blaVIM or blaOXA-48. Multilocus sequence typing data and pulsed-field gel electrophoresis showed that several strains from the same geographical region and hospitals were genetically related.

The Haematological Profile of Patients with Multiple Sclerosis

Background: Patients with multiple sclerosis experience various disabilities, depending on the number and placement of lesions in the brain. Red blood cells with impaired membrane fluidity, as has been reported in patients with multiple sclerosis are known to be further targeted by phospholipase A2 during inflammatory activation. Objectives: The objective of the present study was therefore to investigate the haematological profile of patients with multiple sclerosis and to correlate this with their functional disability and inflammatory status. Methods: Differential full blood counts of 31 patients with multiple sclerosis and 30 age- and gender-matched control subjects were determined on a Beckman Coulter. The functional disability status of each patient was measured using the Kurtzke Expanded Disability Status Scale. C-reactive protein was determined on a Beckman auto-analyser. Results: The haemoglobin was significantly decreased in patients: 13.9 ± 1.40 g/dl, controls: 14.7 ± 1.60 g/dl, P = 0.01, while platelets were increased in patients: 292 ± 133 × 109/l, controls: 258 ± 88.0 × 109/l, P = 0.04. The number of red blood cells correlated inversely with the Kurtzke Expanded Disability Status Scale (R = –0.41;P = 0.02). Platelets correlated inversely with the haemoglobin (P = 0.04) and positively with Visual and Brainstem Scores (P < 0.01, P = 0.07 respectively), but inversely with the Sensory Score (P = 0.02). Conclusions: It is not clear from the results whether the compromised red blood cell profile in patients was due to unknown agents involved in the disease aetiology or from the resulting inflammatory responses, but the inverse correlation between the red blood cell count and the Kurtzke Expanded Disability Status Scale, a measure of neuronal function, suggested a relationship between red blood cell count and disease outcome. Furthermore, the inverse correlation of platelets with the haemoglobin suggested immunological involvement. Platelets, similar to white blood cells, supply fatty acids for pro-inflammatory eicosanoid synthesis.

南非成人社区获得性肺炎管理指南

在南非,由于社区获得性肺炎(community-acquired pneumonia,CAP)的疾病负担增加以及抗菌药物耐药率(antimicrobial resistance,AMR)升高,需要规范抗菌药物处方的标准,因而改善CAP患者的管理水平尤其重要。本指南旨在为临床医生提供CAP患者管理的推荐性建议。对临床医生来说,本次更新纳入了CAP患者管理的重要进展和争议。

南非严重耐多药结核基因型的多样性

背景:严重耐多药结核(XDR-TB)已成为结核病控制的新威胁,但对其流行病学尚不十分了解。目的:采用分子手段研究南非XDR-TB菌株基因型的人群结构组成,从而确定XDR-TB主要是获得性还是原发感染。方法:收集耐多药结核(MDR-TB)患者的痰菌分离株,送至国家参比实验室进行二线抗结核药物的药敏试验。对XDR-TB的分离株进行Spoligotyping分型,并与该分离株的地理来源相匹配。结果:自2005年6月至2006年12月共获得699例MDR-TB患者的分离株,其中101例(17%)菌株耐氧氟沙星(OFX)或卡那霉素(KAN),41例(6%)对二者均耐药(XDR-TB)。Spoligotyping法将XDR-TB分离株共分为17个基因型。结果表现为高度的基因型多样性和地理分布多样性,所以我们估计63%～75%的XDR-TB患者为获得性耐药。结论:获得性严重耐多药可能是导致南非XDR-TB流行的主要机制。因此结核病控制的迫切问题是必须致力于阻止这种潜在的不治之症的传播。

Hepatitis E virus: Western Cape, South Africa

AIM To conduct a prospective assessment of anti-hepatitis E virus(HEV) Ig G seroprevalence in the Western Cape Province of South Africa in conjunction with evaluating risk factors for exposure.METHODS Consenting participants attending clinics and wards of Groote Schuur, Red Cross Children's Hospital and their affiliated teaching hospitals in Cape Town, South Africa, were sampled. Healthy adults attending blood donor clinics were also recruited. Patients with known liver disease were excluded and all major ethnic/race groups were included to broadly represent local demographics. Relevant demographic data was captured at the time of sampling using an interviewer-administered confidential questionnaire. Human immunodeficiency virus(HIV) status was self-disclosed. HEV Ig G testing was performed using the Wantai? assay.RESULTS HEV is endemic in the region with a seroprevalence of 27.9%(n = 324/1161) 95%CI: 25.3%-30.5%(21.9% when age-adjusted) with no significant differences between ethnic groups or HIV status. Seroprevalence in children is low but rapidly increases in early adulthood. With univariate analysis, age ≥ 30 years old, pork and bacon/ham consumption suggested risk. In the multivariate analysis, the highest risk factor for HEV Ig G seropositivity(OR = 7.679, 95%CI: 5.38-10.96, P < 0.001) was being 30 years or older followed by pork consumption(OR = 2.052, 95%CI: 1.39-3.03, P < 0.001). A recent clinical case demonstrates that HEV genotype 3 may be currently circulating in the Western Cape.CONCLUSION Hepatitis E seroprevalence was considerably higher than previously thought suggesting that hepatitis E warrants consideration in any patient presenting with an unexplained hepatitis in the Western Cape, irrespective of travel history, age or ethnicity.

The Impact of Human Immunodeficiency Virus Infection (HIV) on Lymphoma in South Africa

Human immunodeficiency virus (HIV) infection is endemic in South Africa. Non-Hodgkin lymphoma (NHL) occurs with increased frequency in HIV seropositive individuals. The increase in NHL has been more marked in the last decade, with HIV being the major contributor to this increase. More than 70% of the adult NHL patients at Chris Hani Baragwanath Academic Hospital (CHBAH), Soweto, Johannesburg, are HIV seropositive. In addition, HIV has impacted on the clinical presentation—being more aggressive and atypical. Histologically, HIV-NHL typically manifests as B-cell, high grade lymphomas, including diffuse large B-cell lymphoma (DLBCL);Burkitt lymphoma (BL);B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL and plasmablastic lymphoma. The latter two entities, which were previously rare or unknown, have gained prominence in the last decade, occurring primarily in HIV seropositive individuals. HIV-NHL, being associated with all these adverse prognostic factors results in a poorer overall survival.

Prevalence and Antibiotic Profile of Multidrug Resistance Gram-Negative Pathogens Isolated from Wound Infections at Two Tertiary Hospitals in Limpopo Province, South Africa: A Retrospective Study

Background: There is a high mortality and morbidity associated with multidrug resistance pathogens. The high rate of MDR isolates is gradually becoming a threat to the coverage of antibiotics including the clinical outcome of infected patients. Methods: A 5-year laboratory based antibiotic susceptibility data from January 2016 to December 2020 was reviewed to determine the most prevalent MDR pathogens isolated from samples taken from patients with wound infections at Pietersburg and Mankweng Hospitals. Results: A total of 792 pathogens were analyzed. The most prevalent isolates were Klebsiella pneumoniae (23%), Pseudomonas aeruginosa (21.7%), Escherichia coli (16%), Proteus mirabilis (13.5%), Acinetobacter baumannii (9.1%) and Klebsiella oxytoca (3.8%). The overall prevalence of MDR isolates in this study was 38.1%. The distribution of MDR prevalence amongst these isolates was K. pneumoniae (20.8%), P. aeruginosa (18.8%), P. mirabilis (17.5%), E. coli (15.9%) and A. baumannii (8.3%). Of the 9 antibiotic agents tested, trimethoprim sulfamethoxazole, tigecycline and cefepime had the highest levels of resistance. The highest level of resistance was conferred by K. pneumoniae having 63% of isolates identified as MDR. The study could not determine statistical significance of any determinant of MDR. Conclusion: The study revealed that there is high rate of MDR pathogens (38.9%) in Limpopo. Majority of the pathogens were K. pneumoniae from surgical ward, which also conferred high resistance levels. A proportion of the MDR pathogens was identified as A. baumannii CRE pathogens and is noteworthy in implementation aggressive infection prevention and control strategies.

Methicillin Resistant Staphylococcus aureus in Pigs and Pig Breeders in Three Regions of Cameroon

The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porcine methicillin resistant Staphylococcus aureus (P-MRSA) whose carriage and transmission was mainly demonstrated in persons with occupational exposure to pigs. Much uncertainty remains about the public health implications of P-MRSA. To address concerns that exist regarding the zoonotic risk that pig carriers pose to breeders, the prevalence of P-MRSA in pigs and pig breeders was determined among 152 pig breeders in three regions of Cameroon. Materials and Method: Participants in this study came from Adamawa, Far North and Littoral regions of Cameroon. A total of 152 pig breeders or farm workers participated in this study. After having collected some social and cultural data with the aid of a questionnaire, nasal swabs were collected from pigs (n = 275) and their breeders using the standard collection procedures and placed in cooler containing cold accumulators. For each sample, microbiological assays were done as well as antibiotic susceptibility tests. Results: MRSA was isolated from 25 out of 275 pigs sampled (9.09%) and from 32 out of 152 (21.05%) pig breeders sampled;33 breeders (21.71%) were carriers of S. aureus including 32 MRSA and one MSSA. The prevalence of MRSA nasal carriage was 21.05% ± 6.48. A significant negative association between body protection and nasal carriage of MRSA (OR = 0.29, 95% CI [0.093;0.93];p = 0.04) was observed. In each region, similar strains of MRSA were isolated both in pigs and their breeders with the same antibiotic resistant profile. Conclusion: The prevalence of MRSA though not high compared to European countries warrants further research as data on this zoonosis is scarce in our context. As such, transmission of MRSA from pigs to pig breeders or vice-versa constitutes a real danger, and this relationship may be a starting point for MRSA contamination in the community. Moreover, proper use of body protections and antibiotic medications as recommended will be a better protective measure against nasal MRSA carriage.

High Resolution Melting Curve Analysis for Rapid Detection of Pyrazinamide Resistance in Mycobacterium tuberculosis Clinical Isolates

Background: Pyrazinamide (PZA) is one of the most important drugs for tuberculosis (TB) treatment, however, its susceptibility is not routinely tested. High-resolution melting (HRM) curve analysis has been widely used for many applications. In this study, HRM assay was developed and evaluated for the detection of PZA resistance in Mycobacterium tuberculosis clinical isolates. Methods: Ninety five M. tuberculosis clinical isolates with different susceptibility patterns to anti-TB drugs were used to evaluate this assay. Isolates were phenotypically (Bactec MGIT 960) and genotypically (HRM and pncA gene sequencing) analysed for PZA resistance. Results: Bactec MGIT 960 analysis revealed that 29 of the 95 M. tuberculosis isolates were PZA resistant. In comparison to the Bactec MGIT 960, HRM showed a sensitivity of 47.7% and specificity of 74.6%, and the overall agreement between the two methods was 68.4%. Based on DNA sequencing, a correlation of 0.67 (significant at p-value pncA mutations was observed. PZA resistance was strongly associated with multi-drug resistant (MDR)-TB as it was shown in 79.3% of the MDR isolates included in the study. Conclusion: HRM is simple and useful for screening clinical M. tuberculosis isolates for PZA resistance, however, further modifications to improve its performance are required.

Gold Nanorods-mediated Photothermal Therapy Guided by Vascular Interventional Radiation to Inhibit Cancer Metastasis

The purpose of this study was to investigate the inhibitory effect of gold nanorods-mediated photothermal therapy on liver metastasis of colorectal cancer under the guidance of vascular interventional radiology.A total of 80 patients admitted to our hospital from February 2018 to February 2020 were selected and randomly divided into study group and control group with 40 cases each,among which the control group received 125I seed implantation combined with chemotherapy.On this basis,the study group were added the gold nanorods(AuNRs)to the photothermal therapy additionally.The clinical efficacy,postoperative complications and postoperative survival rates of the two groups were compared.The results showed that the total clinical effective rate was 82.5%in the study group,which was significantly better than 67.5%in the control group,and the difference was statistically significant(P<0.05).In addition,the incidence of leukocytosis,nausea,vomiting and delayed diarrhea in the study group was significantly lower than that in the control group,with statistically significant differences(P<0.05).There were no statistically significant differences in the proportion of elevated body temperature,liver dysfunction,or moderate liver pain between the two groups(P>0.05).Therefore,under the guidance of vascular interventional radiology,Au NRs are safe and effective materials for the treatment of liver metastasis of colorectal cancer,which can reduce complications and improve postoperative survival rates.

Ticks, Demographics, Vegetation Cover, and Farmer’s Age Influence Red Meat Production in Resource-Poor Regions of Eastern Cape Province of South Africa

This study presents an integrated examination of livestock production constraints associating with communal farming in six district municipalities (DMs) of the Eastern Cape Province. We collected data on demographic and socio-economic factors from 271 farmers randomly given questionnaires. About 26 Land Redistribution for Agricultural Development (LRAD) owned by communal farmers were surveyed to ascertain the condition of grazing land, meanwhile, tick species and distribution on cattle and goats found in 158 sampling sites of the study area were also recorded. From the results, a total of 34,929 adult ticks belonging to five genera and 10 species were encountered. The most abundant tick genera were Rhipicephalus of the subgenus Boophilus (68.91%), Amblyomma (20.72%), Hyalomma (8.64%), Ixodes (1.22%), and Haemaphysalis (0.51%). By geographic distributions, Amblyomma and Rhipicephalus were common to all DMs, while R. microplus and R. decoloratus were found in the drier regions. From the map plotted for 16 custom feeding centers, lack of marketing channels (23%), poor animal conditions (20%), lack of infrastructure (19%), high price of medicine (14%), shortage of feed (10%), stock theft (8%), and age of animals (too old) to be marketed (6%) are the major shortcomings in red meat production. We found that the associations between gender (χ2 = 31.3481, p < 0.0001), age (χ2 = 32.4889, p < 0.0001), and farming experience (χ2 = 52.7556, p < 0.0001) were significantly (p < 0.05) higher. Additionally, we found that farming commodities were significantly influenced by gender and farming experience. From the surveyed LRAD farms, we observed a higher proportion of increaser II grass species in Alfred Nzo (55.6%), Amathole (53.9%), and Chris Hani (46.4%) DMs. On the other hand, the decreaser grass species were few in Alfred Nzo (16.5%), Amathole (13.8%), and Chris Hani (21.8%). Inferences from the data indicate the need for government and stakeholders’ intervention to farmers through the provision of infrastructures, marketing channels, and training on livestock based programs.

Investigation of the Anti-Mycobacterial Mechanism of Action of 7-Methyljuglone

Objectives: Although the naphthoquinone, 7-methyljuglone (7-MJ), is active against Mycobacterium tuberculosis (MTB) in vitro, neither the cellular site nor mechanism of anti-mycobacterial action of this agent has been identified. The primary objective of the current study was to investigate the mycobacterial outer membrane as a potential target of 7-MJ by measuring the effects of this agent (0.023 - 1.5 mg/L) on microbial ATP levels and uptake of K+ . Methods: Bioluminescence and radiometric (uptake of 86Rb+) procedures were used to assay microbial ATP levels and K+ transport respectively. Results: Exposure of MTB (strain H37Rv) to 7-MJ for 60 min resulted in dose-related decreases in both microbial ATP levels and uptake of 86Rb+ which achieved statistical significance (P + transport.

Molecular Diversity of <i>Staphylococcus aureus</i>from the Nares of Hospital Personnel, HIV-Positive and Diabetes Mellitus Patients in Yaounde Cameroon

Nasal carriage of Staphylococcus aureus has been identified as a risk factor for the development of staphylococcal infections caused by endogenous colonizing strains. Information on the genotypic diversity of Staphylococcus aureus is relevant for managing epidemiological and clinical challenges resulting from the evolutionary differences of this bacterium. The objective of this study was to determine and compare the molecular diversity of Staphylococcus aureus isolates from three high-risk populations in Yaounde, Cameroon. Molecular analysis confirmed that 95% of 100 tested isolates were S. aureus. The mecA and Panton Valentine-Leukocidin (PVL) genes (lukS/F-PV) were detected in 37% (35/95) and 43% (41/95) of isolates respectively and 18% (17/95) of the isolates harboured both the mecA and lukS/F-PV genes. A mixed distribution of both methicillin sensitive S. aureus (MSSA)/PVL and methicillin resistant S. aureus (MRSA)/PVL strains were detected within the study population. Community associated MRSA accounted for 94% (33/35) of the isolates, further classified into allotypes SCCmec type IV 54% (19/35) and SCCmec type V 40% (14/35), while two isolates were hospital associated SCCmec type II strains. A majority of the isolates harboured a single aggressive gene regulator allele agr type I. Pulsed Field Gel Electrophoresis (PFGE) generated 18 pulsotypes that grouped isolates irrespective of the study population. Multilocus Sequence Typing (MLST) of 12 selected isolates was assigned to six pandemic clonal complexes (CC): CC5 (ST5), CC8 [ST8, (n = 3)], CC15 (ST 15), CC25 (ST 25), CC72 [ST72 (n = 2)] and CC121 [ST 121 (n = 2)] and three atypical sequence types ST 508, ST 699 (CC45) and ST 1289 (CC 88). The study population represents an important reservoir for MRSA, MRSA-PVL and MSSA-PVL which could serve as focal point for further dissemination bringing about significant clinical and epidemiological implications. The predominance of SCCmec IV and agr types in this setting warrants further investigation. Isolates were genetically diverse with MLST indicating that pandemic ST8 was predominant. Detection of atypical STs has provided an insight into the necessity for constant monitoring.

Effects of Clarithromycin at Sub-Minimum Inhibitory Concentrations on Early <i>erm</i>B Gene Expression, Metabolic Activity and Growth of an <i>erm</i>(B)-Expressing Macrolide-Resistant Strain of <i>Streptococcus pneumoniae</i>

Aim: To investigate the effects of exposure of a macrolide-resistant [erm (B)-expressing] strain of Streptococcus pneumoniae (strain 2507) to clarithromycin (0.5 and 5 mg/L) added at the outset and 6 hours after initiation of culture on early gene expression, energy metabolism, and growth. Methods: Bacterial growth was determined by turbidometric and colony counting procedures, energy metabolism by measurement of ATP, while analysis of gene expression was performed using reverse transcription-PCR and sequencing. Results: Addition of clarithromycin, at either concentration, at the outset of culture, caused transient suppression of growth of 10 - 12 hours duration, while delayed addition of antibiotic (during the logarithmic phase) resulted in an abrupt halt in growth followed by recovery. These inhibitory effects of clarithromycin on bacterial growth were associated with up-regulation of expression of erm(B), decreased ATP and protein synthesis, and were unaffected by inclusion of either catalase (500 and 1000 kunits/L), or competence-stimulating peptide (CSP-1, 0.5 mg/L). The inhibitory effects could, however, be overcome by pre-exposure of the bacteria to the antibiotic. Moreover, clarithromycin appeared to potentiate the antimicrobial actions of ceftriaxone, at sub-MIC concentrations, for strain 2507. Conclusions: Unlike several other common bacterial pathogens, the full expression of erm(B)-mediated macrolide resistance by the pneumococcus has a slow onset, which is associated with transient susceptibility to macrolides and inhibition of growth.

Phylogeny,ecology and taxonomy of systemic pathogens and their relatives in Ajellomycetaceae(Onygenales):Blastomyces,Emergomyces,Emmonsia,Emmonsiellopsis

The family Ajellomycetaceae(Onygenales)includes mammal-associated pathogens within the genera Blastomyces,Emmonsia,Histoplasma and Paracoccidioides,as well as the recently described genera,Emergomyces that causes disease in immunocompromised hosts,and Emmonsiellopsis,known only from soil.To further assess the phylogenetic relationships among and between members of these genera and several previously undescribed species,we sequenced and analyzed the DNA-directed RNA polymerase II(rPB2),translation elongation factor 3-a(TEF3),b-tubulin(TUB2),28S large subunit rDNA(LSU)and the internal transcribed spacer regions(ITS)in 68 strains,in addition to morphological and physiological investigations.To better understand the thermal dimorphism among these fungi,the dynamic process of transformation from mycelial to yeast-like or adiaspore-like forms was also assessed over a range of temperatures(6–42C).Molecular data resolved the relationships and recognized five major well-supported lineages that correspond largely to the genus level.Emmonsia,typified by Emmonsia parva,is a synonym of Blastomyces that also accommodates Blastomyces helicus(formerly Emmonsia helica).Emmonsia crescens is phylogenetically distinct,and found closely related to a single strain from soil without known etiology.Blastomyces silverae,Emergomyces canadensis,Emergomyces europaeus and Emmonsia sola are newly described.Almost all of the taxa are associated with human and animal disease.Emmonsia crescens,B.dermatitidis and B.parvus are prevalently associated with pulmonary disease in humans or animals.Blastomyces helicus,B.percursus,Emergomyces africanus,Es.canadensis,Es.europaeus,Es.orientalis and Es.pasteurianus(formerly Emmonsia pasteuriana)are predominantly found in human hosts with immune disorders;no animal hosts are known for these species except B.helicus.