Sociodemographic and clinical profile of attempted suicide patients

Introduction

Suicide attempts are common and constitute a serious problem for public health.Thus, it is very important to evaluate risk factors for suicidal behavior.

Objectives

The purpose of this study was to explore the socio-demographic and clinical profile of attempted suicide patients consulting in the psychiatry department in Gabes (southern of Tunisia).

Methods

It was a retrospective descriptive and analytical study covering all patients who had attempted suicide during the period from the 1st of May, 2009 to September 25th, 2020 and who were referred to the psychiatry department in the regional hospital of Gabes. Sociodemographic and clinical data of the patients as well as characteristics of the suicide attemptswere assessed.

Results

Socio-demographic profile of the suicidal consultant in psychiatry department corresponded to a single (73.4%) female (78.8%), with a mean age of 26 years, from an urban area (46%). Suicide attempts were most often by the intentional drug ingestion (67.8%), committed between March and August in 54% of cases. At most of the time, the suicidal person was alone (85%) at home (94%) when he committed his suicidal attempt. He did not communicate his intention to commit suicide in 46% of the cases and only 22 cases (7.9%) notified a person before the suicide attempt and 12.6% afterwards. Suicide behavior was impulsive in 79.5% of the cases and a verbal expression of a desire to die was only noted in 24.5% of cases.

Conclusions

Our results suggest a systematic and specific psychiatric evaluation of any patient who attempts suicide.

Conflict of interest

No significant relationships.

Socio-demographic and clinical features of patients with dementia attended in the psychiatry department

Introduction

Dementia’s prevalence increases due to population aging, it has become a major public health concern.

Objectives

To estimate the incidence of dementia and to describe the socio-demographic and clinical profile of patients attended in the psychiatry department of Gabes (Southern of Tunisia).

Methods

It was a retrospective descriptive study including all the patients who attended for the first time in the psychiatry department of Gabes, from the 1st January, 2010 to December 31, 2018, and who were diagnosed with dementia according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Socio-demographic and clinical data were assessed. The Mini Mental State Examination (MMSE) was used as a neuropsychological examination.

Results

We included 98 patients. The mean annual hospital incidence of dementia was 2.38%. The mean age was 76.5 ± 9.8 years. Patients were married (68%), illiterate (68%) and jobless (42.9%). A family history of dementia was noted in 39.8% of patients. The common cardiovascular comorbidity was high blood pressure (41.8%). Among our patients, 30 (30.6%) were smokers. The mean age of onset of dementia was 73 ± 11 years. The mean duration of untreated dementia was 3 years [3 months to 11 years]. First symptoms were mainly memory disorders (57.3 %) and behavioral disorders (17.3%) The mean MMSE score was 14 ± 4.8. Alzheimer’s disease was the most frequent etiology of dementia (80 cases, 82.7%).

Conclusions

Our study shows a high incidence of dementia and made it possible to draw up a socio-demographic and clinical profile of dementia patients.

Disclosure

No significant relationships.

National Cardiovascular Data Registry-Acute Kidney Injury (NCDR) vs. Mehran risk models for prediction of contrast-induced nephropathy and need for dialysis after coronary angiography in a German patient cohort

BACKGROUND

Contrast-induced nephropathy (CIN) is a major adverse event in patients undergoing coronary angiography. The Mehran risk model is the gold-standard for CIN risk prediction. However, its performance in comparison to more contemporary National Cardiovascular Data Registry-Acute Kidney Injury (NCDR-AKI) risk models remains unknown. We aimed to compare both in this study.

METHODS AND RESULTS

Predictions of Mehran and NCDR-AKI risk models and clinical events of CIN and need for dialysis were assessed in a total of 2067 patients undergoing coronary angiography with or without percutaneous coronary intervention. Risk models were compared regarding discrimination (receiver operating characteristic analysis), net reclassification improvement (NRI) and calibration (graphical and statistical analysis). The NCDR risk model showed superior risk discrimination for predicting CIN (NCDR c-index 0.75, 95% CI 0.72-0.78; vs. Mehran c-index 0.69, 95% CI 0.66-0.72, p < 0.01), and continuous NRI (0.22; 95% CI 0.12-0.32; p < 0.01) compared to the Mehran model. The NCDR risk model tended to underestimate the risk of CIN, while the Mehran model was more evenly calibrated. For the prediction of need for dialysis, NCDR-AKI-D also discriminated risk better (c-index 0.85, 95% CI 0.79-0.91; vs. Mehran c-index 0.75, 95% CI 0.66-0.84; p_NCDRvsMehran < 0.01), but continuous NRI showed no benefit and calibration analysis revealed an underestimation of dialysis risk.

CONCLUSION

In German patients undergoing coronary angiography, the modern NCDR risk model for predicting contrast-induced nephropathy showed superior discrimination compared to the GRACE model while showing less accurate calibration. Results for the outcome 'need for dialysis' were equivocal.

Vaginismus: Sociodemographic profile and cultural aspects

Introduction

Vaginismus is the most common reason for unconsummated marriages in Tunisia.

Objectives

To describe the socio-demographic profile and to explore the clinical and cultural aspects of sexual functioning of women with vaginismus.

Methods

It was a cross-sectional study established over a period of 3 months from the November 1st, 2019 to January 31st, 2020. This study focused on a population of women with vaginismus recruited from outpatient consultations of the hospital’s gynecology and psychiatry departments at the regional hospital of Gabes. We used a pre-established sheet exploring socio-demographic data, medical and gyneco-obstetric history and informations concerning the partner, the marital relationship and the woman’s sexual activity.

Results

35 women were included. They had a mean age of 30 years, jobless (54.5%) and with a secondary or university education (91.1%). The mean duration of marriage was 2.4 years. Partner had mean age of 36 and suffering from sexual dysfunction (21.3%). Among women, 12.5% had been sexually abused, 51.6% had suffered “Tasfih”, 70% had attended discussions about painful defloration. Vaginismus was primary in 85.7% and total in 50% of the cases. About the received thoughts of the women, 40% thought that vaginismus requires medical treatment, 13 of them (40%) thought that the disorder could be resolved spontaneously and 20% believed in a story of witchcraft. 85% consulted a physician and 24.2% a traditional therapist.

Conclusions

Vaginismus seems to be influenced by psychological and sociocultural factors so that a good psychoeducation of brides could reduce the incidence of this sexual disorder.

Conflict of interest

No significant relationships.

Warning signs of suicide attempts and risk of suicidal recurrence

Introduction

Detecting warning signs of suicide attempts is a particular difficult task. However, people who plan to commit suicide almost always announce it to someone in some way.

Objectives

Aims of this study were to describe signs preceding the suicide attempt in a group of suicidal persons and its links with suicidal recurrence.

Methods

It was a retrospective study that included all the patients who attempted suicide during the period from May 1st, 2009 to September 25th, 2020 and who were referred to the psychiatry department of the regional hospital of Gabes. Sociodemographic and clinical data as well as suicidal attempts characteristics were assessed.

Results

278 patients were included (female=78.1%), with mean age of 26. The common suicidal attempt method was intentional drug intoxication (67.8%). At least, one clinical manifestation was reported by 75.2% of suicide patients. The most common signs were the tendency to isolation (47.1%), a change in character or behavior (46.6%), thoughts of death (29.6%), anxiety or agitation (24.8%) and recent worsening of the pre-existing psychiatric symptoms (24.3%). Suicidal recurrence affected 24.8% of patients. It was correlated to the presence of a mental disorder (p<10-3), the presence of reflections on death (p=0.02), the onset of a state of anxiety or agitation (p<10-3), recent worsening of pre-existing psychiatric symptoms (p = 0.001) and verbal expression of suicidal thoughts (p<10-3).

Conclusions

The pre-suicidal syndrome is frequently heralded by changes in the patient’s character or behavior. Some suicidal warning signs are associated with the risk of suicidal recurrence.

Conflict of interest

No significant relationships.

Covid19 pandemic impacts on mental health of tunisian health care workers

Introduction

Covid19 pandemic in Tunisia has disturbed the health system. Health care workers, who were in the frontline to face this disease, had experienced reactions of anxiety, depression and distress.

Objectives

To assess the level of anxiety and depression among health care workers of regional hospital of Gabes (south of Tunisia) and its associated factors.

Methods

We conducted a cross-sectional study, from April 19, 2020, to May 5, 2020 on healthcare workers in Gabes regional Hospital. All hospital departments and units were included. We used a self-administered anonymous questionnaire containing sociodemographic and clinical data. Hospital Anxiety and Depression Scale (HAD) validated in the Tunisian dialectal version was used to assess anxiety and depression.

Results

Among the 289 responding participants, 100 (34.6%) were frontline health care workers directly engaged in managing patients with coronavirus disease. Our study revealed that 43.6% of health care workers were suffering from anxiety and 44.3 % from depression. There was a significant association between anxiety and female gender (p<0.001), being married (p=0.006), mental health conditions (p<0.001) especially anxiety disorders (p<0.001) and depressive disorders (p=0.03), personal medical history of dysthyroidism (p=0.013) and smoking (p=0.005). Nurses experienced more likely anxiety symptoms than other occupation (p=0.021). There was significant relationship between depression and female gender (p<0.001), married status (p=0.02), age under 50 (p=0.032) and mental health conditions (p<0.001) such as anxiety disorders (p=0.001) and depressive disorders (p=0.013).

Conclusions

It is crucial to provide care for health care workers with mental health problems during their struggle with covid19.

Sleep disorders among health care workers practicing in emergency department in south tunisia

Introduction

Sleep disorders are the most common health problem among the health care staff, mainly those who perform night shifts.

Objectives

To assess the prevalence of sleep disorders among health care workers in emergency department and to determine its associated factors.

Methods

It was a cross-sectional study, including health care workers assigned to emergency ward and intensive care unit of Hedi Chaker and Habib Bourguiba hospitals in Sfax and regional hospital of Kebili, during the first six months of 2017. We used an anonymous and confidential self-administered questionnaire. We used hospital anxiety and depression scale (HAD) to assess anxiety and depression. Sleep quality was assessed by the Pittsburgh Sleep Quality Index and day time sleepiness by the Epworth Sleepiness Scale.

Results

240 nurses were included. Mean age was 37 years-old, 59.2% were female and 64.2% were married and 79.2% assured night shifts. The prevalence of sleep disorders was 70.4%. Sleep difficulties were significantly correlated with anxiety (p=0.001) and depression (p=0.02). In multivariate study, sleep disorders were related to the absence of leisure activity (OR=0.42 [0.19-0.94]; p=0.035) and anxiety (OR=3 [1.4-6.1]; p=0.002). 40.8% of nurses experienced drowsiness. Sleepiness was significantly correlated with the absence of leisure activities (p=0.04) and with psychiatric family history (p=0.02). In the multivariate study, sleep disorders were correlated with female gender (OR=0.43 [0.19-0.9]; p=0.042) and with no leisure activity (OR=2.6 [1.2-5.6]; p=0.01).

Conclusions

Sleep disorders were common among emergency nurses, in order of that; working conditions should be improved to provide less stressful conditions for nurses.

Conflict of interest

No significant relationships.

Modern NCDR and ACTION risk models outperform the GRACE model for prediction of in-hospital mortality in acute coronary syndrome in a German cohort

BACKGROUND AND PURPOSE

Risk prediction with the Global Registry of Acute Coronary Events (GRACE) risk model is guideline-recommended in acute coronary syndrome (ACS) patients. However, the performance of more contemporary scores derived from ACTION (Acute Coronary Treatment and Intervention Outcomes Network) and National Cardiovascular Data (NCDR) registries remains incompletely understood. We aimed to compare these models in German ACS patients.

METHODS AND RESULTS

A total of 1567 patients with (Non-)ST-segment elevation myocardial infarction (NSTEMI: 1002 patients, STEMI: 565 patients) undergoing invasive management at University Hospital Düsseldorf (Germany) from 2014 to 2018 were included. Overall in-hospital mortality was 7.5% (NSTEMI 3.7%, STEMI 14.5%). Parameters for calculation of GRACE 1.0, GRACE 2.0, ACTION and NCDR risk models and in-hospital mortality were assessed and risk model performance was compared. The GRACE 1.0 risk model for prediction of in-hospital mortality discriminated risk superior (c-index 0.84) to its successor GRACE 2.0 (c-index 0.79, p_{GRACE1.0vsGRACE2.0} = 0.0008). The NCDR model performed best in discrimination of risk in ACS overall (c-index 0.89; p_ACTIONvsNCDR < 0.0001; p_GRACEvsNCDR < 0.0001) and showed superior performance compared to GRACE in NSTEMI and STEMI subgroups (p_GRACEvsNCDR both < 0.02). ACTION and GRACE risk models performed comparable to each other (both c-index 0.84, p_{GRACEvsACTION} = 0.68), with advantages for ACTION in NSTEMI patients (c-index 0.87 vs. 0.84 (GRACE); p_{GRACEvsACTION} = 0.02). ACTION and GRACE 2.0 showed the most accurate calibration of all models.

CONCLUSIONS

In a contemporary German patient population with ACS, modern NCDR and ACTION risk models showed superior performance in prediction of in-hospital mortality compared to the gold-standard GRACE model.

Standardized risk management in catheterization procedures for non-ST-segment elevation myocardial infarction: associations with in-hospital clinical outcomes

Introduction and purpose

Patient risk in non-ST-segment elevation myocardial infarction (NSTEMI) depends on clinical setting, individual patient variables and procedural characteristics. Standardized risk-adjusted periprocedural management for catheterization procedures using a Standard Operating Procedure (SOP) was investigated to evaluate associations with in-hospital clinical outcomes.

Methods

In 01/2018, our heart center established an SOP for coronary catheterization procedures in NSTEMI, targeting 1) standardized pre-procedural risk assessment using National Cardiovascular Data Registry (NCDR) risk models, and 2) standardized post-procedural risk-adjusted safety measures, including advanced patient monitoring (intermediate/intensive care) and use of vascular closure devices. All patients presenting with invasively-managed NSTEMI in 2018 were retrospectively evaluated for SOP-based pre-procedural risk scoring, SOP-based post-procedural management and in-hospital clinical outcomes of mortality, major bleeding (MB, according to BARC ≥3) and acute kidney injury (AKI, according to KDIGO).

Results

A total of 430 patients (age 72±12 years, 71% male, BMI 27±5) presenting with NSTEMI from 01 to 12/2018 were included, 9.8% presented in cardiogenic shock and 4.7% had suffered a preclinical cardiac arrest. Overall in-hospital mortality was 3.7%, MB occurred in 6.5%. 207 patients (48.1%, SOP+ group) had received both 1) pre-procedural risk assessment and 2) post-procedural risk-adjusted safety measures; the other 223 patients (51.9%, SOP- group) had not received either 1) or 2). There were no significant differences in baseline characteristics and prior-existing medical conditions between groups, however, significantly more patients in SOP- group were treated in emergency settings (39.9% vs. 21.7%, p=0.004). However, significantly more patients in SOP- were treated in emergency settings at higher risk (39.9% (SOP-) vs. 21.7% (SOP+); p&lt;0.001). In univariate analysis, all in-hospital clinical outcomes of mortality (1.4% (SOP+) vs. 5.8% (SOP-); p=0.016), MB (2.9% (SOP+) vs. 9.9% (SOP-); p=0.003) and AKI were significantly lower in the SOP+ group (15.9% (SOP+) vs. 24.2% (SOP-); p=0.033). After correction for the difference in risk between groups due to emergency settings by multivariate logistic regression analysis, MB remained significantly lower in SOP+ (p=0.02), while mortality (p=0.14) and AKI (p=0.19) were not significantly associated with SOP-status anymore.

Conclusion

Standardized risk management in invasively managed NSTEMI was associated with significantly lower rates of in-hospital major bleedings.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Junior Clinician Scientist Track, Medical faculty, Heinrich-Heine-University Düsseldorf, Germany

Quantification of cell surface proteins with bispecific antibodies

Flow cytometry is an established method for fast and accurate quantitation of cellular protein levels and requires fluorescently labeled antibodies as well as calibration standards. A critical step for quantitation remains the production of suitable detection antibodies with a precisely defined ratio of antigen-binding sites to fluorophores. Problems often arise as a consequence of inefficient and unspecific labeling which can influence antibody properties. In addition, the number of incorporated fluorophores necessitates a special normalization step for quantitation. To address these problems, we constructed different mono- and bivalent bispecific antibodies with binding site(s) for the cell surface antigens, cMET, EGFR1/HER1, ErbB2/HER2 or ErbB3/HER3 and with an additional digoxigenin-binding single-chain Fv fusion. The fluorophore Cy5 was covalently coupled to digoxigenin and quantitatively bound by the bispecific antibody. A panel of tumor cell lines was assessed under different culture conditions for absolute receptor expression levels of the indicated antigens and the data were set in relation to mRNA, gene count and immunoblot data. We could reproducibly quantify these receptors, omit the otherwise required normalization step and demonstrate the superiority of a 1 + 1 bispecific antibody. The same antibodies were also used to quantify the number of proteins in intracellular vesicles in confocal microscopy. The antibodies can be stored like regular antibodies and can be coupled with different digoxigenin-labeled fluorophores which makes them excellent tools for FACS and imaging-based experiments.

Opioid-induced constipation in advanced illness: safety and efficacy of methylnaltrexone bromide

Constipation, one of the major side effects of opiates used in palliative care, can impair patients’ quality of life to a point where it prevents sufficient pain control. Methylnaltrexone is a novel μ-receptor antagonist, which does not pass the blood brain barrier. It is licensed to treat opiate induced constipation for patients with advanced diseases. This review article presents an overview of pharmacology and safety of its application, evidence of its efficacy and economic aspects of its use in clinical practice. Available data are limited but strongly suggest that methylnaltrexone causes laxation in less than 24 hours for at least half of those patients over the first two weeks of usage without impairing pain control or causing serious adverse effects. To avoid danger of gastrointestinal perforation it is contraindicated for patients at risk for that complication. More research is needed to evaluate its long-term efficacy and economic impact.

Influence of a Capping Layer on the Mechanical Properties of Copper Films

The substrate curvature technique was employed to study the mechanical properties of 0.6 μm and 1.0 μm Cu films capped with a 50 nm thick Si3N4 layer and to compare them with the mechanical properties of uncapped Cu films. The microstructures of these films were also investigated. Grain growth, diffusional creep and dislocation processes are impeded by the cap layer. This is evident in the form of high stresses at high temperatures on heating and at low temperatures on cooling. At intermediate temperatures on heating and cooling, stress plateaus a relatively low stresses exist. This can be explained by the so-called Bauschinger effect. A film thickness dependence of the stresses in the film could not be observed for capped Cu films.

Observation and Modelling of Electromigration-Induced Void growth in Al-Based Interconnects

Accelerated electromigation tests on unpassivated, pure aluminum interconnects were performed. The failure mechanisms were observed by interrupting the tests and exanming the conductor lines using an SEM. Because the metal thin film was subjected to a so-called laser reflow process before patterning, grain boundaries were visible in the SEM as thermal grooves. Voids were observed to move along the line and to grow in a transgranular manner, and a characteristic asymmetric void shape was identified which seems to be related to the failure mechanism. It is argued that substantial progress in modelling and understanding of electromigration failure can be made by consideration of such void shape effects.

Influence of Film Thickness and Capping Layer on the Mechanical Properties of Copper Films

Substrate curvature and X-ray technique were used to study the mechanical properties of Cu films. Stress-temperature curves were measured using both methods. An additional analysis of the X-ray peak width allows us to estimate grain size and dislocation density as a function of temperature. It can be shown that a capping layer changes the mechanical properties of a Cu film strongly and that in capped films dislocation processes seem to be more important than diffusion at high temperatures.

Measurement of Thermally-Induced Strains in Polycrystalline Al Thin Films on Si Using Convergent Beam Electron Diffraction

Strains in polycrystalline Al films grown on oxidized Si wafers were measured using convergent beam electron diffraction (CBED). CBED patterns were acquired on a Zeiss EM 912 TEM equipped with an imaging energy filter and CCD camera. HOLZ line positions in the (000) CBED disk were matched using an automated refinement procedure. A sensitivity to variations in lattice parameter of approximately 0.00007 nm was obtained. Strong deviations from a simple equibiaxial strain, perfect [111] texture model were observed.

Observation and Modelling of Electromigration-Induced Void Growth In AI-Based Interconnects

Accelerated electromigation tests on unpassivated, pure aluminum interconnects were performed. The failure mechanisms were observed by interrupting the tests and examining the conductor lines using an SEM. Because the metal thin film was subjected to a so-called laser reflow process before patterning, grain boundaries were visible in the SEM as thermal grooves. Voids were observed to move along the line and to grow in a transgranular manner, and a characteristic asymmetric void shape was identified which seems to be related to the failure mechanism. It is argued that substantial progress in modelling and understanding of electromigration failure can be made by consideration of such void shape effects.

A new acylated flavone glycoside from the fruits of Stocksia brauhica

Phytochemical investigations of the fruits of Stocksia brauhica (Sapindaceae) resulted in the isolation of a new acylated flavone glycoside. Its structure of the new compound brauhenefloroside D (1) was established as 3-O-[(alpha-L-rhamnopyranosyl)oxy]-7-O-[(acetyl)-beta-D-glucopyranosyl (1 --> 4)]-[6-O-(4-hydroxy-E-cinnamoyl)-beta-D-glucopyranosyl-(1 --> 2)-alpha-L-rhamnopyranosyl)-oxy]-kaempferol. The structure elucidation of the new compound was based primarily on 1D and 2D NMR analysis, including COSY, HMBC and HMQC correlations.

The effect of membrane potential on the development of chemical osmotic pressure in compacted clay

When clay soils are subjected to salt concentration gradients, various interrelated processes come into play. It is known that chemical osmosis induces a water flow and that a membrane potential difference develops that counteracts diffusive flow of solutes and osmotic flow of water. In this paper, we present the results of experiments on the influence of membrane potential on chemical osmotic flow and diffusion of solutes and we show how we are able to derive the membrane potential value from theory. Moreover, the simultaneous development of water pressure, salt concentration and membrane potential difference are simulated using a model for combined chemico-electroosmosis in clays. A new method for short-circuiting the clay sample is employed to assess the influence of electrical effects on flow of water and transport of solutes.

p73alpha is a candidate effector in the p53 independent apoptosis pathway of cisplatin damaged primary murine colonocytes

AIMS

Colonocytes were derived from wild-type (wt) and p53 deficient mice to investigate p53 dependent and independent death pathways after cisplatin treatment, and the role of p53 in growth regulation of primary, untransformed epithelial cells.

METHODS

Wt and p53 null colonocytes were exposed to cisplatin and DNA synthesis, apoptosis, and p53, p21, and p73 expression were investigated after six, 12, and 24 hours. Major p73 isoforms were identified by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

Cisplatin treated wt cells exhibited cell cycle arrest, whereas p53 null cells continued to synthesise DNA, although both cell types died. Apoptosis was significantly higher in cisplatin treated wt and p53 null colonocytes than in controls at all timepoints, although apoptosis was lower in cisplatin treated p53 null colonocytes than in wt cells. p53 expression was upregulated in cisplatin treated wt colonocytes. p21 expression was high and remained unchanged in cisplatin treated wt cells, although it was reduced in the absence of p53. p73 was investigated because it could account for p53 independent p21 expression and p53 independent death. RT-PCR detected full length p73alpha. p73 transcript levels remained unchanged, whereas p73 protein accumulated in the nucleus of cisplatin treated cells, irrespective of genotype.

CONCLUSIONS

p53 is essential for cell cycle arrest, but not apoptosis in primary murine colonocytes. Apoptosis is reduced in cisplatin treated p53 null cells. Nuclear accumulation of endogenous p73 after cisplatin treatment suggests a proapoptotic role for p73alpha in the absence of p53 and collaboration with p53 in wt colonocytes.

Evaluation for synergistic suppression of T cell responses to minor histocompatibility antigens by chloroquine in combination with tacrolimus and a rapamycin derivative, SDZ-RAD

The 4-aminoquinolines, chloroquine and hydroxychloroquine, can suppress chronic graft-versus-host disease (GVHD) following blood and marrow transplantation (BMT) in mice and humans, respectively. We hypothesized that chloroquine in combination with tacrolimus and the rapamycin derivative SDZ-RAD can synergistically suppress T cell responses and antigen-presenting cell (APC) function in vitro. We used the APC-dependent C57BL/6 anti-BALB.B T cell response and APC-independent anti-CD3epsilon antibody-induced response to evaluate the role of synergism between chloroquine and tacrolimus or SDZ-RAD on each component of a T cell response to minor histocompatibility antigens. We found that chloroquine with tacrolimus had a greater synergistic suppression of APC-dependent compared to the APC-independent T cell responses, with a combination index (CIx) for 50% inhibition by mean effect analysis of 0.16 and 0.50, respectively (a lower number indicates greater suppression). By contrast, chloroquine with SDZ-RAD had a similar CIx between the two responsed 0.50 vs0.45) suggesting only T cell suppression. Synergy between chloroquine and SDZ-RAD involved a direct effect on T cell cytokine production, whereas synergism between chloroquine and tacrolimus was due to an effect on both T cells and APCs. We conclude that the renal-sparing 4-aminoquinolines may be used syneristically with immunosuppressive drugs currently used for BMT.

Cyclin D1 overexpression in colorectal carcinoma in vivo is dependent on beta-catenin protein dysregulation, but not k-ras mutation

Cyclin D1 protein overexpression is commonly found in colorectal carcinomas (CRCs) and is associated with a poorer prognosis, but the mechanism underlying overexpression remains uncertain. Both dysregulation of beta-catenin protein expression and k-ras mutation have recently been shown to promote cyclin D1 expression in human in vitro and rodent in vivo studies. In this study, 53 sporadic CRCs were examined by immunohistochemistry for cyclin D1 and beta-catenin protein expression, and with PCR and direct DNA sequencing for k-ras gene status. The study also addressed whether cyclin Dl overexpression might associate with poorer prognosis because of a relationship with poorer response to 5-fluorouracil (5FU) chemotherapy. Cyclin D1 overexpression was demonstrated in 34/53 (64%) CRCs, was significantly associated with higher Dukes' stage, and was particularly prominent at the invasive edges of carcinomas. Furthermore, cyclin D1 overexpression was always and only seen in association with nuclear expression of beta-catenin. There were no significant associations between cyclin D1 overexpression and k-ras mutation or response to 5FU. Amongst 17 microsatellite unstable CRCs, a smaller proportion of tumours showed cyclin D1 overexpression (18%), but again cyclin D1 overexpression was only seen in cases showing nuclear beta-catenin expression. In conclusion, beta-catenin protein dysregulation, but not k-ras mutation, appears to be required for cyclin D1 overexpression in colorectal carcinoma in vivo.

Epigenetic inactivation of RASSF1A in lung and breast cancers and malignant phenotype suppression

BACKGROUND

The recently identified RASSF1 locus is located within a 120-kilobase region of chromosome 3p21.3 that frequently undergoes allele loss in lung and breast cancers. We explored the hypothesis that RASSF1 encodes a tumor suppressor gene for lung and breast cancers.

METHODS

We assessed expression of two RASSF1 gene products, RASSF1A and RASSF1C, and the methylation status of their respective promoters in 27 non-small-cell lung cancer (NSCLC) cell lines, in 107 resected NSCLCs, in 47 small-cell lung cancer (SCLC) cell lines, in 22 breast cancer cell lines, in 39 resected breast cancers, in 104 nonmalignant lung samples, and in three breast and lung epithelial cultures. We also transfected a lung cancer cell line that lacks RASSF1A expression with vectors containing RASSF1A complementary DNA to determine whether exogenous expression of RASSF1A would affect in vitro growth and in vivo tumorigenicity of this cell line. All statistical tests were two-sided.

RESULTS

RASSF1A messenger RNA was expressed in nonmalignant epithelial cultures but not in 100% of the SCLC, in 65% of the NSCLC, or in 60% of the breast cancer lines. By contrast, RASSF1C was expressed in all nonmalignant cell cultures and in nearly all cancer cell lines. RASSF1A promoter hypermethylation was detected in 100% of SCLC, in 63% of NSCLC, in 64% of breast cancer lines, in 30% of primary NSCLCs, and in 49% of primary breast tumors but in none of the nonmalignant lung tissues. RASSF1A promoter hypermethylation in resected NSCLCs was associated with impaired patient survival (P =.046). Exogenous expression of RASSF1A in a cell line lacking expression decreased in vitro colony formation and in vivo tumorigenicity.

CONCLUSION

RASSF1A is a potential tumor suppressor gene that undergoes epigenetic inactivation in lung and breast cancers through hypermethylation of its promoter region.

Most microsatellite unstable sporadic colorectal carcinomas carry MBD4 mutations

The MBD4 gene is involved in the repair of mutation at methyl-CpG dinucleotides. In microsatellite unstable tumours MBD4 can itself be mutated at an exonic polynucleotide tract. By analysing DNA from microdissected tumour samples we have found that both frequency and pattern of mutation are more significant than originally reported.

Somatic frameshift mutations in the MBD4 gene of sporadic colon cancers with mismatch repair deficiency

Defects of mismatch repair are thought to be responsible for carcinogenesis in hereditary non-polyposis colorectal cancer and about 15% of sporadic colon cancers. The phenotype is seen as microsatellite instability and is known to be caused either by mutations in mismatch repair genes or by aberrant methylation of these genes stabilizing their downregulation. Lack of repair of microsatellite sequence errors, created during replication, leads to a mutation-prone phenotype. Where mutations occur within mononucleotide tracts within exons they cause translation frameshifts, premature cessation of translation and abnormal protein expression. Such mutations have been observed in the TGFbetaRII, BAX, IGFIIR, MSH3 and MSH6 genes in colon and other cancers. We describe here frameshift mutations affecting the gene for the methyl-CpG binding thymine glycosylase, MBD4, in over 40% of microsatellite unstable sporadic colon cancers. The mutations all appear heterozygous but their location would ensure truncation of the protein between the methyl-CpG binding and glycosylase domains, thus potentially generating a dominant negative effect. It is thus possible that such mutations enhance mutation frequency at other sites in these tumours. A suggestion has been made that MBD4 (MED1) mutations may lead to an increased rate of microsatellite instability but this mechanism appears unlikely due to the nature of mutations we have found.

Pulmonary tuberculosis presenting as mass lesions and simulating neoplasms in adults

In a review of the chest X-rays and medical records of 597 cases of culture- or biopsy-proven pulmonary tuberculosis (PTB; age range 1.5-72 years), seen over a period of 6 years (1991-97), 26 patients had radiographic patterns unusual for PTB. These patterns were mass-like densities simulating neoplasms, chronic lower lobe airspace opacities without adenopathy, mediastinal adenopathy without parenchymal airspace opacities and bronchopleural fistula without other radiographic abnormalities. The most common of these unusual radiographic patterns was mass-like densities, most of which were initially and mistakenly diagnosed as neoplasms. These masses, seen in 11 adult patients, form the basis of this report. Two children aged 1.5 and 2 years also had tuberculous mass densities initially diagnosed as neurogenic tumour and round pneumonia, respectively. They have been excluded from the present series, and form the subject of another report. The masses were lower lobe predominant and were not usually associated with fibro-productive satellite lesions or with calcification or cavitation. In view of the recent resurgence of PTB and the importance of chest X-rays in its diagnosis and management, this rare radiographic pattern needs to be emphasized.

Cloning of a breast cancer homozygous deletion junction narrows the region of search for a 3p21.3 tumor suppressor gene

Chromosome 3p abnormalities and allele loss are frequent in lung and breast cancers, and several lung cancer cell lines exhibit homozygous deletions of 3p indicating potential sites of tumor suppressor genes at regions 3p21.3, 3p14.2 and 3p12. We have identified and characterized a new 3p21.3 homozygous deletion in a breast cancer cell line and the primary tumor that overlaps those previously described in small cell lung cancer (SCLC). This homozygous deletion is approximately 220 kb in length and represents a somatically acquired change in the primary breast cancer. Cloning and sequencing of the breakpoint demonstrated that this resulted from an interstitial deletion and precisely pinpoints this deletion within the three SCLC homozygous deletions previously reported. This deletion significantly narrows the minimum common deleted region to 120 kb and is distinct from the previously reported region that suppresses tumor formation of the murine A9 fibrosarcoma cells. These findings suggest that a common homozygous deletion region on 3p21.3 is important in both lung and breast cancers. It is likely that this very well characterized region either contains one tumor suppressor gene common to both tumor types or two closely linked tumor suppressor genes specific for each tumor.

Group practice vs. solo practice--a dentist's view

The percentage of dentists joining group practices has increased sharply in the past fifteen years. Many advantages to practicing in a group setting including social, clinical, and financial aspects have contributed to this change. Solo practice has become increasingly difficult for new dentists. Market forces as well as insurance changes have accelerated the transition to group practice. Multispecialty groups have particular features that have allowed them to become much more popular. The advent of dental practice management companies has fueled the growth of multispecialty groups and has created new business opportunities for dental practice owners.

Immune suppression by lysosomotropic amines and cyclosporine on T-cell responses to minor and major histocompatibility antigens: does synergy exist?

BACKGROUND

Using murine models, we have shown that the lysosomotropic amine, chloroquine, is effective in the prevention of graft-versus-host disease (GVHD) mediated by donor T cells reactive with recipient minor histocompatibility antigens (MiHCs). Because lysosomotropic amines can suppress major histocompatibility complex (MHC) class II antigen presentation, their mechanism of action is potentially different from current immune suppressant drugs used to control GVHD such as cyclosporine.

METHODS

We investigated the use of cyclosporine and the lysosomotropic amines chloroquine and hydroxychloroquine in combination for additive or synergistic immunosuppression on T-cell responses in vitro to MiHC and MHC in mice.

RESULTS

We found that similar concentrations of chloroquine and hydroxychloroquine suppress the T-cell response to MiHC in mice (C57BL/6 anti-BALB.B) and that lysosomotropic amines in combination with cyclosporine result in synergistic suppression of a proliferative response to MiHC. Similar suppression and synergy appear to be present in an alloreactive response (C57BL/6 anti-BALB/c). Direct inhibition by chloroquine of T-cell proliferative responses induced by anti-CD3epsilon in the absence of antigen-presenting cells is present at higher concentrations than that required to suppress responses to MiHC or MHC. Chloroquine appears to induce decreased T-cell viability at high concentrations. This effect does not appear to be due to decreased T-cell production of interleukin-2 or interferon-gamma. At lower concentrations (<25 microg/ml), chloroquine can also decrease the ability of antigen-presenting cells to stimulate an a C57BL/6 anti-BALB/c T-cell response and can inhibit MHC class II expression after activation with lipopolysaccharide.

CONCLUSIONS

Lysosomotropic amines in combination with cyclosporine appear to be synergistic in the suppression of T-cell proliferation to MiHC and MHC. Use of chloroquine in combination with cyclosporine may result in improved control of GVHD.

The human homolog of the rodent immediate early response genes, PC4 and TIS7, resides in the lung cancer tumor suppressor gene region on chromosome 3p21

Recently, human chromosome band 3p21.3 was shown to undergo overlapping homozygous deletions in several small cell lung cancer lines further defining a putative tumor suppressor gene(s) region. We report the cloning and mutational analysis of a novel human gene, SKMc15, from the commonly homozygously deleted region in three small cell lung cancer lines (NCI-H1450, NCI-H740, GLC20). It has 11 exons ranging in size from 50 to 541 bp with an open reading frame of 442 amino acids. The gene covers 7 to 10 kb of genomic DNA; the message of 1.8 to 2 kb is expressed in all analyzed fetal and adult human and mouse tissues including heart, brain, placenta, lung liver, skeletal muscle, kidney, testis and pancreas and in small cell and non-small cell cancer lines. The intron/exon boundaries were used to analyze the gene for mutations by exon PCR-SSCP sequencing in 60 small cell lung cancer cell lines. No loss-of-function mutations were detected. The cDNA sequence has high homology, 75% at the protein level, to the rat early response gene PC4 and its murine homolog TIS7. In addition, the known partial sequence of the putative mouse interferon beta2 (64 amino acids) gene is highly conserved in PC4/TIS7 (94%) and in SKMc15 (83%) at the amino acid level. The sequence TAAAT, which is thought to be involved in mRNA degradation, is present in the 3' UTR of SKMc15 and in the 3' UTR of PC4 and TIS7 genes.

Synergy between lysosomotropic amines and cyclosporin A on human T cell responses to an exogenous protein antigen, tetanus toxoid

Previously, it has been shown that the lysosomotropic amine, chloroquine, is effective in the prevention of graft-versus-host disease (GVHD) using murine models. Because chloroquine and hydroxychloroquine suppress MHC class II antigen presentation, their mechanism of action is different to other immune suppressant drugs (cyclosporin A) currently used to control GVHD. It is possible that the use of cyclosporin A and chloroquine in combination may have an additive or synergistic effect on T cell responses to antigens presented in the context of MHC class II. We investigated the effects of chloroquine or hydroxychloroquine in combination with cyclosporin A on human T cell responses in vitro to tetanus toxoid, an exogenous protein antigen dependent on MHC class II presentation for proliferative responses. We demonstrate that similar levels of chloroquine and hydroxychloroquine suppress human T cell responses to tetanus toxoid and that the use of either agent in combination with cyclosporin A results in synergistic suppression. Evaluation for a direct effect by the lysosomotropic amines on T cells, in the absence of antigen presenting cells, revealed that there was inhibition of T cell responses but only at high concentrations. No significant decrease or increase was seen in surface MHC II or invariant chain expression or in cytoplasmic invariant chain after exposure to chloroquine. Thus, lysosomotropic amines in combination with cyclosporin A are synergistic in suppression of T cell proliferation. Use of these agents in combination with cyclosporin A may improve control of graft-versus-host disease.

Human semaphorins A(V) and IV reside in the 3p21.3 small cell lung cancer deletion region and demonstrate distinct expression patterns

Semaphorins and collapsins make up a family of conserved genes that encode nerve growth cone guidance signals. We have identified two additional members of the human semaphorin family [human semaphorin A(V) and human semaphorin IV] in chromosome region 3p21.3, where several small cell lung cancer (SCLC) cell lines exhibit homozygous deletions indicative of a tumor suppressor gene. Human semaphorin A(V) has 86% amino acid homology with murine semaphorin A, whereas semaphorin IV is most closely related to murine semaphorin E, with 50% homology. These semaphorin genes are approximately 70 kb apart flanking two GTP-binding protein genes, GNAI-2 and GNAT-1. In contrast, other human semaphorin gene sequences (human semaphorin III and homologues of murine semaphorins B and C) are not located on chromosome 3. Human semaphorin A(V) is translated in vitro into a 90-kDa protein, which accumulates at the endoplasmic reticulum. The human semaphorin A(V) (3.4-kb mRNA) and IV (3.9- and 2.9-kb mRNAs) genes are expressed abundantly but differentially in a variety of human neural and nonneural tissues. Human semaphorin A(V) was expressed in only 1 out of 23 SCLCs and 7 out of 16 non-SCLCs, whereas semaphorin IV was expressed in 19 out of 23 SCLCs and 13 out of 16 non-SCLCs. Mutational analysis in semaphorin A(V) revealed mutations (germ line in one case) in 3 of 40 lung cancers. Our data suggest the need to determine the function of human semaphorins A(V) and IV in nonneural tissues and their role in the pathogenesis of lung cancer.