Tuberculin skin testing and QuantiFERON™-TB Gold Plus positivity among household contacts in Vietnam

SETTING

TB infection (TBI) is diagnosed using the technique-dependent tuberculin skin test (TST) or costly, more accurate interferon-gamma release assays. The TST (⩾10 mm) threshold was indicated by previous research among household contacts in Vietnam, but routine implementation with a different tuberculin reagent showed unexpectedly low TST positivity.

OBJECTIVE

TST (⩾5 mm and ⩾10 mm) results were compared to QuantiFERON™-TB Gold Plus (QFT) results in household contacts during community campaigns in 2020 and 2021.

DESIGN

This was a cross-sectional multi-center implementation study.

RESULTS

Among 1,330 household contacts in 2020, we found a TBI prevalence of 38.6% (QFT), similar to TST ⩾5 mm (37.4%) and higher than TST ⩾10 mm (13.1%). QFT+/TST+ was higher for TST ⩾5 mm (20.7%) than TST ⩾10 mm (9.4%). QFT was not discordant with TST ⩾5 mm (McNemar's test = 0.6, P = 0.5) but was discordant with TST ⩾10 mm (McNemar's test = 263.9, P < 0.01). Older age and Southern region increased odds for positive TST ⩾5 mm and QFT with weaker associations for TST ⩾10 mm. Agreement and discordance were similar in 2021 for 1,158 household contacts.

CONCLUSION

Tuberculin reagents affect TST positivity rates. High TB burden countries should monitor reliability of TBI diagnosis, including tuberculin potency, cold chain, and TST technique to optimize eligibility for TB preventive treatment.

Real-world eligibility for vericiguat according to trial, guideline, and labelling eligibility criteria: data from the Swedish Heart Failure Registry

Introduction

The VICTORIA trial demonstrated the efficacy and safety of vericiguat in patients with worsening heart failure (HF) and an ejection fraction (EF) of &lt;45%. Trial selection criteria might limit the external validity, and the perceived low generalisability may be an underlying reason for poor implementation of new treatments.

Purpose

We calculated the proportions of patients who would be eligible for vericiguat according to trial, guideline, and labelling scenarios in a large and unselected real-word HF population, and compared eligible to ineligible populations for patient characteristics and outcomes.

Methods

From the Swedish HF Registry (SwedeHF), 41,635 patients with EF&lt;40% recorded between May 2000 and December 2018 were considered. We applied the VICTORIA trial's selection criteria, the 2021 European Society of Cardiology (ESC) guidelines' recommendation, and the regulatory labelling of vericiguat according to the Food and Drug Administration and European Medicines Agency. Outcome rates (cardiovascular [CV] and non-CV death, and first HF hospitalisation [HFH]) were compared between eligible and ineligible patients using exact Poisson test with a significance level of 5%. We also analysed 60,351 patients with EF&lt;50% for the trial scenario.

Results

Eligibility for vericiguat based on the trial, guideline, and labelling criteria were 21.2%, 25.7%, and 44.5%, respectively (Figure 1). The criteria with major impacts on eligibility were: 1) in the trial scenario - inclusion criteria: recent HFH (within 6 months) and elevated NT-proBNP (met by 47.5% and 74.4% of the population, respectively), exclusion criteria - nitrate use (14.0%); 2) in the guideline scenario: recent HFH and HF duration longer than 6 months (as a proxy for optimal medical therapy) (47.5% and 57.6%, respectively); 3) in the labelling scenario: recent HFH (47.5%). In patients with EF&lt;50%, trial eligibility was slightly lower, and the impact of selection criteria was overall similar to those with EF&lt;40%. Overall, eligible patients were older, less likely to be female, had more severe HF and comorbidities, and had greater mortality and morbidity (Figure 1).

Conclusion

In a large and contemporary real-world cohort of HF with EF&lt;40%, eligibility for vericiguat according to the trial and guideline scenarios was limited, i.e. ∼20–25%, whereas it was higher according to the labelling scenario, i.e. ∼45%. The VICTORIA trial's selection criteria successfully selected a HF population enriched for CV events but also with a higher risk of non-CV events, which is consistent with more severe HF and comorbidities in eligible vs. ineligible patients, but the requirement for recent worsening HF also rendered many patients ineligible. Our findings might provide insights for designing more inclusive and feasible future trials and might help stakeholders assess the consequences of future trial eligibility.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Bayer AG

“Adipose-derived mesenchymal stem cell therapy for the management of female sexual dysfunction: Literature reviews and study design of a clinical trial”

Hormone imbalance and female sexual dysfunction immensely affect perimenopausal female health and quality of life. Hormone therapy can improve female hormone deficiency, but long-term use increases the risk of cardiovascular diseases and cancer. Therefore, it is necessary to develop a novel effective treatment to achieve long-term improvement in female general and sexual health. This study reviewed factors affecting syndromes of female sexual dysfunction and its current therapy options. Next, the authors introduced research data on mesenchymal stromal cell/mesenchymal stem cell (MSC) therapy to treat female reproductive diseases, including Asherman’s syndrome, premature ovarian failure/primary ovarian insufficiency, and vaginal atrophy. Among adult tissue-derived MSCs, adipose tissue-derived stem cells (ASCs) have emerged as the most potent therapeutic cell therapy due to their abundant presence in the stromal vascular fraction of fat, high proliferation capacity, superior immunomodulation, and strong secretion profile of regenerative factors. Potential mechanisms and side effects of ASCs for the treatment of female sexual dysfunction will be discussed. Our phase I clinical trial has demonstrated the safety of autologous ASC therapy for women and men with sexual hormone deficiency. We designed the first randomized controlled crossover phase II trial to investigate the safety and efficacy of autologous ASCs to treat female sexual dysfunction in perimenopausal women. Here, we introduce the rationale, trial design, and methodology of this clinical study. Because aging and metabolic diseases negatively impact the bioactivity of adult-derived MSCs, this study will use ASCs cultured in physiological oxygen tension (5%) to cope with these challenges. A total of 130 perimenopausal women with sexual dysfunction will receive two intravenous infusions of autologous ASCs in a crossover design. The aims of the proposed study are to evaluate 1) the safety of cell infusion based on the frequency and severity of adverse events/serious adverse events during infusion and follow-up and 2) improvements in female sexual function assessed by the Female Sexual Function Index (FSFI), the Utian Quality of Life Scale (UQOL), and the levels of follicle-stimulating hormone (FSH) and estradiol. In addition, cellular aging biomarkers, including plasminogen activator inhibitor-1 (PAI-1), p16 and p21 expression in T cells and the inflammatory cytokine profile, will also be characterized. Overall, this study will provide essential insights into the effects and potential mechanisms of ASC therapy for perimenopausal women with sexual dysfunction. It also suggests direction and design strategies for future research.

Depression, stigma and quality of life in people with drug-susceptible TB and drug-resistant TB in Vietnam

BACKGROUND: Drug resistance poses a major barrier to global control of TB - a leading infectious cause of death. Depression and stigma occur commonly among people with TB. However, the relationship between drug-resistant forms of TB, depression and stigma are not well understood.OBJECTIVE: To compare depression, stigma and health-related quality of life (HRQoL), among people with drug-susceptible TB (DS-TB) and multidrug-resistant TB (MDR-TB).METHODS: A cross-sectional study of people treated for DS-TB and MDR-TB in four provinces of Vietnam. The survey included a stigma scale (Vietnamese Tuberculosis Stigma Scale), depression scale (9-item Patient Health Questionnaire) and HRQoL scale (Functional Assessment of Chronic Illness Therapy - Tuberculosis). Differences between the two populations were compared using linear regression.RESULTS: Eighty-one people with DS-TB and 315 people with MDR-TB participated in the study. People with MDR-TB had a higher prevalence of depression than those with DS-TB (difference 17.8%, χ² 8.64). The mean depression and stigma scores were higher for people with MDR-TB than those with DS-TB (adjusted difference [AD] 8.6 and 7.6 respectively). People with MDR-TB reported lower HRQoL than those with DS-TB (AD -23.8).CONCLUSION: Depression and stigma are common among people with TB in Vietnam. Strategies to prevent and treat depressive symptoms and stigma in people with TB are critical to a holistic, patient-centred approach to care.

An experience in prenatal diagnosis via QF-PCR of a female child with a 9.9 Mb pure deletion at 18p11.32-11.22

Quantitative Fluorescent - Polymerase Chain Reaction (QF-PCR) is a rapid prenatal diagnosis test for 21, 18, 13 and sex chromosomal aneuploidy detection. However, it could not detect partial trisomy or partial monosomy of those chromosomes. Here, we report a 19-month-old Vietnamese female with a 9.9 Mb pure deletion of chromosome 18 at 18p11.32-11.22 confirmed by next generation sequencing. The patient was short statured with facial dysmorphic features as well as motor skill and speech delays. First trimester screening showed high risk of trisomy 21 with only increased nuchal translucency (NT 3.9 mm) by ultrasound as an indication. Prenatal diagnosis by QF-PCR from amniotic DNA revealed normal disomy. Noticeably, two short tandem repeat (STR) markers D18S391 and D18S976 located on 18p exhibited uninformative patterns (one peak). Thus, our case suggested that the combination of both D18S391 and D18S976 markers with uninformative patterns in QF-PCR for prenatal diagnosis and increased NT in the first trimester ultrasound may be a significant indication of 18p monosomy.

Post-treatment Mortality Among Patients With Tuberculosis: A Prospective Cohort Study of 10 964 Patients in Vietnam

BACKGROUND

Tuberculosis is the leading infectious cause of death. Steep reductions in tuberculosis-related mortality are required to realize the World Health Organization's "End Tuberculosis Strategy." However, accurate mortality estimates are lacking in many countries, particularly following discharge from care. This study aimed to establish the mortality rate among patients with pulmonary tuberculosis in Vietnam and to quantify the excess mortality in this population.

METHODS

We conducted a prospective cohort study among adult patients treated for smear-positive pulmonary tuberculosis in 70 clinics across Vietnam. People living in the same households were recruited as controls. Participants were re-interviewed and their survival was established at least 2 years after their treatment with an 8-month standardized regimen. The presence of relapse was established by linking identifying data on patients and controls to clinic registries. Verbal autopsies were performed. The cumulative mortality among patients was compared to that among a control population, adjusting for age and gender.

RESULTS

We enrolled 10964 patients and 25707 household controls. Among enrolled tuberculosis patients, 9% of patients died within a median follow-up period of 2.9 years: 342 (3.1%) during treatment and 637 (5.8%) after discharge. The standardized mortality ratio was 4.0 (95% confidence interval 3.7-4.2) among patients with tuberculosis, compared to the control population. Tuberculosis was the likely cause of death for 44.7% of these deceased patients.

CONCLUSIONS

Patients treated for tuberculosis had a markedly elevated risk of death, particularly in the post-treatment period. Interventions to reduce tuberculosis mortality must enhance the early detection of drug-resistance, improve treatment effectiveness, and address non-communicable diseases.

Association of TP53 gene codon 72 polymorphism with Helicobacter pylori-positive non-cardia gastric cancer in Vietnam

INTRODUCTION

This research aimed to determine the association of the combination of H. pylori infection and TP53 codon 72 polymorphism with non-cardia gastric cancer (GC) in Vietnam.

METHODOLOGY

A total of 164 patients with non-cardia GC and 164 patients with peptic ulcer disease or functional dyspepsia in controls matched by sex and age were enrolled. H. pylori infection was diagnosed by rapid urease test and polymerase chain reaction (PCR). The cagA gene-positivity and vacA sm subtypes were determined by multiplex PCR. Genotypes of TP53 codon 72 polymorphism were determined by PCR-restriction fragment length polymorphism.

RESULTS

The prevalence of H. pylori infection in GC and control group were 61.6% and 55.4%, respectively. The rates of cagA-positive strains in the two H. pylori-positive groups were 80.2% and 71.4%, respectively. There was no statistically significant difference in TP53 codon 72 genotype distribution between GC group (frequencies of Arg/Arg, Arg/Pro and Pro/Pro genotypes were 31.1%, 43.3% and 25.6%, respectively) and controls (29.3%, 52.4% and 18.3%, respectively), p = 0.172. The significant difference in genotype distribution was observed in recessive model (Pro/Pro vs Arg/Arg + Arg/Pro) when stratifying by H. pylori infection (OR = 2.02, 95% CI 1.03-3.96, p = 0.041) and by cagA-positivity (OR = 2.33, 95% CI 1.07-5.07, p = 0.032).

CONCLUSIONS

This study suggests a synergistic interaction between H. pylori infection, especially cagA-positive H. pylori, and Pro/Pro genotype of TP53 codon 72 polymorphism might play a significant role in the pathogenesis of GC in the Vietnamese population.

First evidence of association between past environmental exposure to dioxin and DNA methylation of CYP1A1 and IGF2 genes in present day Vietnamese population

During the Vietnam War, the United States military sprayed over 74 million litres of Agent Orange (AO) to destroy forest cover as a counterinsurgency tactic in Vietnam, Laos and Cambodia. The main ingredient was contaminated by 2,3,7,8-tetrachlorodibenzo-paradioxin (TCDD). DNA methylation (DNAm) differences are potential biomarker of environmental toxicants exposure. The aim of this study was to perform a preliminary investigation of the DNAm levels from peripheral blood of the present-day Vietnamese population, including individuals whose parents, according to historical data, were exposed to AO/TCDD during the war. 94 individuals from heavily sprayed areas (cases) and 94 individuals from non-sprayed areas (controls) were studied, and historical data on alleged exposure of parents collected. 94 cases were analysed considering those whose father/parents participated in the war (N = 29) and considering the place of residence of both parents (64 living in sprayed areas versus 30 in non-contaminated areas). DNAm levels in CYP1A1 and IGF2 genes were measured (MALDI-TOF technology). The analyses showed that: 1) one CpG site in the CYP1A1 and one in the IGF2 gene showed significant differences in DNAm levels between cases and controls; 2) the CYP1A1 region resulted to be hypomethylated (in 9 out of 16 sites/units; p-val<0.01) in 29 individuals whose father/parents participated in the war in the spray zones; 3) we showed that the place of residence of both parents influenced methylation levels of the CYP1A1 and IGF2 genes (p-val<0.05). In conclusion this study indicates that past environmental exposure to dioxin (AO/TCDD) shapes the DNAm profile of CYP1A1 and that the place of living for parents in former spray zones influences DNAm of CYP1A1 and IGF2 genes. These results open the way to new applications of DNAm as potential biomarker(s) of past human exposure to dioxin.

Helicobacter pylori 23S rRNA gene mutations associated with clarithromycin resistance in chronic gastritis in Vietnam

Introduction: Data about the prevalence of the A2142C, A2142G, and A2143G mutations in 23S rRNA gene is still limited. The aim of this study was to determine the prevalence of these mutations in 23S rRNA gene of H. pylori vietnamese strains. Methodology: One hundred and sixty-nine patients with H. pylori-positive chronic gastritis were examined. H. pylori was detected by rapid urease test and Polymerase chain reaction (PCR). Total DNA was extracted from gastric biopsy specimens. A2142C, A2142G, and A2143G mutations were detected by DNA sequencing and PCR-restriction fragment length polymorphism (PCR-RFLP). Results: A2143G mutation was detected in 36.1% of samples, A2142G mutation in 3.6%, while A2142C mutation was not found in any case. The mixture of wild-type and mutation strains was found in 50% of specimens with A2142G, in 23% of specimens with A2143G mutation. There was no association of 23S rRNA gene point mutations with gender or age. However, an association between the heterogeneity of mutation and age was evidenced, with mean age of the group of pure A2143G higher than the group of wild-type/A2143G mixture, and rate of the wild-type/A2143G mixture higher in patients under 40 years of age. Conclusion: A2143G mutation was prominent, while A2142C mutation was not found in the 23S rRNA gene. PCR-RFLP has revealed a reliable assay allowing a rapid and cost-effective detection of clarithromycin-resistant strains. This is useful in countries as Vietnam with high prevalence of clarithromycin-resistance before choosing optimal therapy for H. pylori eradication.

Tuberculosis and HIV co-infection in Vietnam

Tuberculosis (TB) and human immunodeficiency virus (HIV) infection are leading causes of disease and death in Vietnam, but TB/HIV disease trends and the profile of co-infected patients are poorly described.

METHODS

We examined national TB and HIV notification data to provide a geographic overview and describe relevant disease trends within Vietnam. We also compared the demographic and clinical profiles of TB patients with and without HIV infection.

RESULTS

During the past 10 years (2005-2014) cumulative HIV case numbers and deaths increased to 298,151 and 71,332 respectively, but access to antiretroviral therapy (ART) improved and new infections and deaths declined. From 2011-2014 routine HIV testing of TB patients increased from 58.9% to 72.5% and of all TB patients diagnosed with HIV in 2014, 2,803 (72.4%) received ART. The number of multidrug resistant (MDR)-TB cases enrolled for treatment increased almost 3-fold (578 to 1,532) from 2011-2014. The rate of HIV co-infection in MDR and non-MDR TB cases (51/1,532; 3.3% vs 3,774/100,555; 3.8%; OR 0.77, 95% CI 0.7-1.2) was similar in 2014.

CONCLUSIONS

The care of TB/HIV co-infected patients have shown sustained improvement in Vietnam. Rising numbers of MDR-TB cases is a concern, but this is not "driven" by HIV co-infection.

Tuberculosis and HIV co-infection-focus on the Asia-Pacific region

Tuberculosis (TB) is the leading opportunistic disease and cause of death in patients with HIV infection. In 2013 there were 1.1 million new TB/HIV co-infected cases globally, accounting for 12% of incident TB cases and 360,000 deaths. The Asia-Pacific region, which contributes more than a half of all TB cases worldwide, traditionally reports low TB/HIV co-infection rates. However, routine testing of TB patients for HIV infection is not universally implemented and the estimated prevalence of HIV in new TB cases increased to 6.3% in 2013. Although HIV infection rates have not seen the rapid rise observed in Sub-Saharan Africa, indications are that rates are increasing among specific high-risk groups. This paper reviews the risks of TB exposure and progression to disease, including the risk of TB recurrence, in this vulnerable population. There is urgency to scale up interventions such as intensified TB case-finding, isoniazid preventive therapy, and TB infection control, as well as HIV testing and improved access to antiretroviral treatment. Increased awareness and concerted action is required to reduce TB/HIV co-infection rates in the Asia-Pacific region and to improve the outcomes of people living with HIV.

Patients' beliefs and behaviors related to treatment adherence in patients with asthma requiring maintenance treatment in Asia

Objectives

To identify patients’ beliefs or behaviors related to treatment adherence and to assess association between asthma control and adherence in Asian patients with asthma.

Methods

We conducted a cross-sectional observational study of adult patients with asthma from specialist clinics in six Asian countries. Patients who were deemed by their treating physicians to require a maintenance treatment with an inhaler for at least 1 year were recruited. Patients completed a 12-item questionnaire related to health beliefs and behaviors, the 8-item Morisky Medication Adherence Scale (MMAS-8), the Asthma Control Test (ACT™), and the Standardized Asthma Quality of Life Questionnaire (AQLQ-S).

Results

Of the 1054 patients recruited, 99% were current users of inhaled corticosteroids. The mean ACT score was 20.0 ± 4.5 and 64% had well-controlled asthma. The mean MMAS-8 score was 5.5 ± 2.0 and 53% were adherent. Adherence was significantly associated with patients’ understanding of the disease and inhaler techniques, and with patients’ acceptance of inhaler medicines in terms of benefits, safety, convenience, and cost (p < 0.01 for all). In multivariate analysis, three questions related to patients’ acceptance of inhaler medicines remained significantly associated with poor adherence, after adjusting for potential confounders: “I am not sure inhaler type medicines work well” (p = 0.001), “Taking medicines more than once a day is inconvenient” (p = 0.002), and “Sometimes I skip my inhaler to use it over a longer period” (p < 0.001).

Conclusions

Our study showed that patients’ acceptance of the benefits, convenience and cost of inhaler medications have a significant impact on treatment adherence in the participating Asian countries.

Reliability and validity of the Vietnamese Vineland Adaptive Behavior Scales with preschool-age children

This study was conducted to examine an adaptation of the Vineland Adaptive Behavior Scale (VABS) [Sparrow, S. S., Balla, D. A., & Cicchetti, D. V. (1984). The Vineland Adaptive Behavior Scales. Circle Pines, MN: America Guidance Service; Sparrow, S. S., Balla, D. A., & Cicchetti, D. V. (2005). Vineland Adaptive Behavior Scales Second Edition Survey Forms Manual. AGS Publishing] and its psychometric properties in Vietnamese culture. The 1984 version of VABS was translated and adapted to form the Vietnamese version of the Vineland Adaptive Behavior Scales (VVABS). The scale was administered to 120 Vietnamese mothers of non-disabled preschool-age children enrolled in kindergarten programs. It was found that the VVABS has acceptable levels of internal consistency reliability and construct validity, and could discriminate successfully between Vietnamese children with intellectual disabilities from those of typical development. The results that were comparable to the VABS indicate a successful adaptation of the construct and measure of adaptive behavior to a non-western culture.

Amidino benzimidazole inhibitors of bacterial two-component systems

Amidino benzimidazoles have been identified as inhibitors of the bacterial KinA/Spo0F two-component system (TCS). Many of these inhibitors exhibit good in vitro antibacterial activity against a variety of susceptible and resistant Gram-positive organisms. The moiety at the 2-position of the benzimidazole was extensively modified. In addition, the regioisomeric benzoxazoles, heterocyclic replacements for the benzimidazole, have been synthesized and their activity against the TCS evaluated.

CD44 and its v6 spliced variant in lung carcinomas: relation to NCAM, CEA, EMA and UP1 and prognostic significance

CD44 is a polymorphic family of cell surface glycoproteins that was recently reported to have important role in cell adhesion and migration as well as modulation of cell-matrix interactions. Thus, expression of CD44 has been proposed to be associated with malignant behavior of tumors like invasive growth and formation of metastasis. The expression of CD44s and its v6 isoform (CD44v6) was determined immunohistochemically in 106 lung tumors of various histophenotypes, degrees of differentiation, and clinical stages. The results were compared with the expression of NCAM, CEA, EMA and UP1 and with clinicopathological parameters including patients' survival. CD44s was expressed in all histophenotypes of non-small cell lung carcinomas (NSCLC) with tendency being squamous cell lung carcinoma (SqCC) > bronchioloalveolar adenocarcinoma (BAC) > conventional adenocarcinoma (ConAC) (91, 66.7 and 38.9%, respectively). Almost identical distribution of positivity revealed CD44v6 in all three subgroups of NSCLC mentioned above (91, 66.7 and 36.1%, respectively). In the subgroup of neuroendocrine tumors, CD44s and CD44v6 were restrictedly expressed in small cell lung carcinomas (2/14 tumors), while all 3 typical carcinoids were strongly positive for these markers. Expression of NCAM and CEA was significantly higher in adenocarcinoma subgroup than those in SqCC subgroup (45.7 and 75% vs. 14.8 and 39%, respectively). NCAM expression was also significantly different in BACs and in ConACs (69.2 vs. 36.4%, p < 0.05). The expression of CD44 was related to the differentiation of SqCC. The carcinomas with keratinization were CD44 positive. Adenocarcinomas producing mucin were CD44 negative. The expression of CD44, NCAM, CEA, EMA and UP1 did not correlate with lymph node metastasis and disease stage. CD44V6 was the only marker that its expression was closely related to patients' survival. The absence CD44v6 but not CD44s in NSCLC group was associated with significantly longer survival of patients compared to patients with CD44v6 positive tumors. This difference was even higher in tumors negative for CD44v6 and simultaneously NCAM and/or CEA positive. The data of this study suggest that CD44v6 might be an independent prognostic factor in NSCLC. Moreover, our data give another evidence of diverse role of CD44 in the differentiation and progression of non-small cell lung carcinomas and neuroendocrine carcinomas of the lung.

Expression of cyclin D1, Ki-67 and PCNA in non-small cell lung cancer: prognostic significance and comparison with p53 and bcl-2

Uncontrolled cell proliferation is the hallmark of malignant tumours. Thus, the proliferative potential of tumour cells is an important prognostic factor. However, evaluation of the prognostic significance of the expression of proteins involved in regulation of cell proliferation remains controversial. In the present study, expression of Ki-67, PCNA and cyclin D1 was estimated in a group of 89 surgically resected non-small cell lung carcinomas using immunohistochemistry. The results were compared with expression of bcl-2 and p53 and with clinicopathological parameters including patients' survival. Ki-67 and PCNA were found to be moderately and highly expressed in 39% and 44% of the tumours, respectively. There was a strong correlation between Ki67 and PCNA expression. Forty five of 88 tumours (51%) showed overexpression of cyclin D1. Surprisingly, cyclin D1 was mainly localized in the cytoplasm and only a small group of tumours (9/88, 10%) showed nuclear staining as well. Bcl-2 and p53 expression was observed in 69% and 30% of the tumours, respectively. All these markers were found to be independent of clinicopathological parameters, except for Ki-67 and bcl-2 expression, which was associated with squamous cell carcinomas. It is concluded that none of the markers that were studied can be used as an independent prognostic factor, whereas the following combinations of markers may have favourable prognostic value: p53 positivity and low Ki-67 expression, p53 positivity and lack of cyclin D1 expression, bcl-2 positivity and low Ki-67 expression, and lack of cyclin D1 expression and low Ki-67 expression.

Synthesis and inhibitory activity of novel tri- and tetracyclic quinolines against topoisomerases

A series of isoindolo[2,1-a]- and pyrrolo[1,2-a]quinolines were designed and synthesized for DNA-gyrase and topoisomerase-II inhibition studies. Some of the compounds showed significant activity against the enzymes.

DNA gyrase inhibitory and antimicrobial activities of some diphenic acid monohydroxamides

The synthesis and inhibitory activity against DNA gyrase of a series of diphenic acid monohydroxamides 4a-f are described. A protocol of two biological assays showed conclusively that inhibition occurs specifically at the DNA-DNA gyrase complex and is not attributable to nonspecific inhibition. In the enzyme assays, 4c was potent as the prototypical quinolone, nalidixic acid (1), with an IC50 value of 58.3 micrograms/mL compared to 52 micrograms/mL for 1. MIC activity against bacterial strains showed a systematic drop for all compounds relative to 1. For compounds 4c-e, the addition of PMBN produced dramatic increases in MIC activity indicating that activity is likely to be related to membrane transport. Molecular modeling of 4a indicates that the diphenic acid monohydroxamides can bind to the DNA-DNA gyrase complex in a similar fashion as that hypothesized for the quinolone series according to the hypothesis suggested by Shen et al. but may not self-associate by pi-pi stacking. In contrast to the quinolone series, as the diphenic acid monohydroxamides are shown by molecular mechanics minimizations to be nonplanar, they may present novel approaches for chemotherapeutic intervention with a potential for decreased side effects.

Synthesis and 5-lipoxygenase inhibitory activities of some novel 2-substituted 5-benzofuran hydroxamic acids

A series of 2-substituted benzofuran hydroxyamic acids were synthesized as rigid analogs of simple (benzyloxy)phenyl hydroxamates, evaluated for their in vitro and in vivo 5-lipoxygenase activity and found to be potent inhibitors of the enzyme. Substituents which enhanced lipophilicity near the 2-position of the benzofuran nucleus increased inhibitor potency but reduced oral activity. Incorporation of small polar substituents such as methoxymethylene, hydroxymethylene, and amino (urea) on the acyl group led to more consistent oral activity. The most potent inhibitors of this series in vitro were N-hydroxy-N-[1-(2-phenyl-5-benzofuranyl)-ethyl]furancarboxamide (12) and methyl 5-[N-hydroxy-N-[1-(2-(3,4,5-trimethoxyphenyl)-5-benzofuranyl]ethyl]-5- oxopentanoate (17), both with IC50 values of 40 nM, and in vivo the most potent compound was N-hydroxy-N-[1-(2-phenyl-5-benzofuranyl)ethyl]urea, 20, with an ED50 = 10.3 mg/kg.

Novel bishydroxamic acids as 5-lipoxygenase inhibitors

Two series of novel bishydroxamic acids 2 and 3 (types A and B) were synthesized and tested for inhibition of 5-lipoxygenase from rat basophile leukemia (RBL) cells. Both series were potent inhibitors of the isolated enzyme but only the type B reverse hydroxamic acids possessed significant oral activity. The most potent compound, orally, was 3a, [IC50 = 270 nM; ED50 = 1.86 mg/kg], which compares favorably with the clinically useful 5-lipoxygenase inhibitor, zileuton. Unlike known hydroxamic acid inhibitors, the oral activity in this series appears to be associated with the second hydroxamic acid group. The corresponding monohydroxamic acids retained inhibitor potency, in vitro, with reduced oral activity in a mouse zymosan peritonitis model. Compound 4e [IC50 = 7 nM], a monohydroxamic acid derivative related to 3a, is among the most potent inhibitors of the isolated enzyme yet to be reported.