A Southern addiction evaluation project: investigating the impact of addiction through a survey HBSC based

Background

Adolescence is a critical phase of development characterized by numerous physical, psychological and social changes. During this stage, individuals may engage in experimentation and risky behavior, leading to increased vulnerability to addiction. This article aims to present the results of a survey based on the HBSC (Health Behavior in School-aged Children) surveillance model in a province of Southern Italy for primary and secondary school students.

Methods

We conducted a prospective study from March 2020 to April 2023 through the administration of a questionnaire to students of the healthcare faculties of the University of Messina and primary and secondary school students, composed of 19 items and based on HBSC surveillance.

Results

We collected a total of 664 questionnaires. We found that smoking habits increase with age: approximately 31% of secondary school students declare they are real smokers compared to 40% of HCP students. At least once, in the three study groups, students experienced alcohol consumption at different rates, with younger students having a greater propensity to drink than older students. Fortunately, in our sample, no middle school students had tried cannabis. At the same time there is a surprising decrease in gambling in all categories compared to national data.

Conclusions

The presence of addictive behaviors in our sample was found to be widespread despite being in line with the national trend. Furthermore, we have observed a reduction in recent years which needs to be investigated to assess the reasons. Primary prevention is probably the main weapon in the hands of politicians and must be applied early in school and community settings to reduce prevalence.

Study-related stress, perceived stress and quality of life among healthcare university students

Background

Many studies have shown that the stress level among healthcare university students is often as high as in workers who experience burnout. Our study investigated if it is possible to observe the burnout syndrome in these kind of students, able to significantly alter the quality of life, their approach to daily activities and relationship life.

Methods

The study was conducted through the administration of an anonymous questionnaire, distributed online through messaging apps, during the breaks between lessons. It was formulated using the perceived stress scale (PSS) in its short formula in order to evaluate feelings and thoughts and the WHOQOL-AGE, in order to evaluate the quality of life.

Results

The sample consisted of 292 university students aged between 18 and 49, with an average age of 22,42 ± 4,65. 16.4% does not often feel able to control the important things in life, 42.8% is often unable to manage personal problems. The PSS score of all our university students showed a high stress level in 6.2%, an average stress level in 57.2% and low stress level in 36.6%. The WHOQOL score shows that 42% had a high quality of life and only 4% had a poor quality of life, 54% had an intermediate quality of life and half of the sample was unsatisfied with the way he felt every day.

Conclusions

Many students (63.4%) are subjected to stress study-related, even if does not affect their quality of live, therefore not perceiving it as negative. There is a gender difference: females have a higher level of stress than men. Two thirds of the sample has an average or high stress level; only a third has a low grade. Stress prevention in young university students must begin through a new way of teaching, even if a certain amount of stress study-related is stimulant.

"Vaccinate your child for best protection": attitude towards vaccination in a group of pregnant women

BACKGROUND

Although the benefits and importance of vaccination before and right after pregnancy, are well known, vaccination coverage among pregnant women remains very low. The aim of our study was to evaluate pregnant women's knowledge and attitude towards vaccination.

STUDY DESIGN

A cross sectional study was performed from October 2018 to June 2019 at the University of Messina.

METHODS

We gave pregnant women >18 years old a non-self-compiling paper questionnaire. We stratified the sample according to age (<30 and >30 years old), marital status (single/divorced, in a relationship and married) and level of education (<8 and >8 years of school attendance). All possible correlations between collected data were analysed using software R.

RESULTS

The sample included 156 women (mean age 32±0.49 years old). Only 1.4% of the subjects were aware of all the vaccines indicated for children. Luckily, 86.7% of the sample had a positive attitude, believing in the effectiveness and safety of immunization, despite a limited lack of confidence and a belief in false myths was expressed by some of the subjects. Interestingly, results showed that information about vaccination were more frequently obtained from family/friends (52.6%), mass media (49.1%), blogs/forums (19.3%), rather than from medical institutions (only 17.5%) or the family physician (only 35.0%), reflecting the quality of the information obtained.

CONCLUSIONS

Our results proved that a general positive attitude emerged among our sample towards vaccination, however, correct information was not always provided to women, making it a crucial issue for public health in the future.

Adherence to the three Italian screening in a sample of women (and men) in the Southern Italy

INTRODUCTION

Although scientific evidence shows the numerous benefits of screening programs, in Italy. There is a great disparity between the regional coverage of the North and South despite the screening programs have been activated for several years in all regions even with territorial differences.

OBJECTIVE

The aim of our study was to evaluate the knowledge and adherence to different screenings in the population, the influence exercised by the local health authority the role of the general practitioner in advising and referring patients to screening tests and the main causes of refuse.

MATERIAL AND METHODS

The study was carried out, from December 2019 to May 2020, through the administration of anonymous self-filled "ad hoc" questionnaires to women and men over 26 years old.

RESULTS

in our sample 36% have never performed a breast check and 39% of the interviewees never had a mammogram; for cervical cancer 25% did not ever perform screening and 65% did not have an indication by GP. The worst result was found for colorectal cancer (only 27% of the sample performed the screening). The role of GP was fundamental for and similar to other studies, was fundamental in fact,similar to other studies the most frequent reported reasons for the non-execution of screening were the lack of physicians' advice, follwed by lack of time, the most frequent reported reasons for the non-execution of screening were the lack of physicians' advice, a lack of time, fear of cancer and embarrassment at visiting a gynaecologist.

DISCUSSION AND CONCLUSIONS

the study carried out found that despite the knowledge of the oncological disease and the possibilities of prevention is fairly rooted in the population, adherence to the screening is quite inadequate, especially as regards colorectal cancer.

Mediterranean diet: knowledge and adherence in Italian young people

INTRODUCTION

In November 2010 the Mediterranean Diet was recognized by the UNESCO as Intangible Cultural Heritage of Humanity. It is an heritage that brings together the dietary habits of the peoples of the Mediterranean countries, consolidated over the centuries remained almost unchanged until the 1950s. Numerous scientific studies have also shown that the Mediterranean Diet is an healthy diet that helps to prevent the main chronic diseases such as cardiovascular diseases, diabetes, bulimia and obesity and thanks to the antioxidant power of olive oil combined with vegetables consumption, an important means of cancer prevention. The aim of our study was to investigate the knowledge and the adherence to the Mediterranean diet of young people living in the Mediterranean area.

MATERIALS AND METHODS

The survey was carried out by administering a web-based anonymous questionnaire from March to May 2019 to Italian young people. In this survey we asked for socio-economic conditions, knowledge, awareness and adherence to the Mediterranean diet (through the KIDMED test) both in childhood and at present time. Parental educational status and family income were used as indicators of socio-economic status (SES).

RESULT

The sample was made up by 507 Italian young people between the ages of 17 and 35 (123 males and 384 females), with an average age of 22.88 years (DS 7.02). Only 11.4% knew the Mediterranean diet. During childhood 70.8% of respondents had breakfast and 58% ate fruit and vegetables daily. Today they have maintained the correct eating habits, in fact, 71.2% had breakfast, 60.2% ate fruit and 64.7% ate vegetables. In addition, only 48.3% eat fish and the majority of respondents consume carbohydrates (76.9%). To a lesser extent they consume junk foods like candy and various snacks (18.1%) or fast food meals (9.1%). Moreover, we asked for physical activity and we found that 48.9% did it. We found age, exercise and sex high significant variables (p<0.01). Higher adherence to MD was found in older interviewees.

CONCLUSION

Our study we found high knowledge to a Mediterranean diet into 90.5% of the sample and poor adherence into 23.5% of them, medium into 53.4% while higher only in 23.1% of the interviewees. Lower adherence was found among those who do not engage in physical activity and the two regressor with higher weight on the adherence to MD were "eat at home "and "eat fruit and vegetables". Furthermore, in our sample more increased the age more increased adherence to traditional diet models.

Definition of a novel vaccination pathway in PLWHA: experience of a Southern University Hospital

Background

At the end of 2018 across the globe there are ∼37.9 million people with HIV/AIDS also thanks to the use of HAART which led to an increase in life expectancy. The Italy Immunization Plan 2017-19 recommend vaccines to these patients but a protocol still isn't present. Moreover, despite the availability of effective vaccines, coverage remained very low for many reasons including problems with privacy. The objectives of this study were a) the appliance of a shared clinical pathway between the “Immunization Center of Hospital Hygiene Operating Unit” and the “HIV/AIDS Disease Prevention, Diagnosis and Treatment Center of Infectious Diseases Operating Unit” b) the increase in vaccination coverage and the evaluation of side effects.

Methods

A prospective study was conducted from Oct 2019 to Feb 2020 at the G. Martino University Hospital of Messina. In particular, of the 138 patients followed by the Infectious Diseases OU, after evaluation of their immune status, 62% were enrolled in this study. Following the acquisition of informed consent, we collected socio-anagraphical data and we started the free administration of vaccines by providing an hoc calendar in the Immunization Center. Statistical analysis was performed with R software.

Results

The sample was represented by 86 patients (74% males and 26% females, 21% foreigners and 79% Italian, mean age=40±13.6 SD). We didn't observe drop out and no differences were observed for local/systemic AEs generally reported. We obtained an increase of vaccination coverage with a total of 74 doses administered for flu (+164%) and 240 for other vaccines (+172%). In particular, we immunized a total of 74% of patients for HPV (2% in 2018), 42% for HAV (28% in 2018), 37% for HBV (28% in 2018), 58% for pneumococcal (21% in 2018), 54% for meningococcal ACWY and B (0% in 2018).

Conclusions

The undertook clinical pathway showed the relevance of specific management of these patients and the need to increase the vaccination offer.

Key messages

The immunization in people living with HIV is priority to reduce the risk of infectious disease. It’s important to implement a shared clinical pathway to increase vaccination rates of these patients. The application of the protocol had an high impact in patients' adhesion to vaccination also thanks to the chance of accessing to the service in a comfortable setting and suitable to protect privacy.

The role of water distribution system in HCAIs

Introduction

The water distribution system in hospitals may constitute a source of healthcare-associated infections. Understanding the means of acquisition, sources and reservoirs of nosocomial pathogens is crucial for developing methods to reduce the incidence of nosocomial infections. The aim of our study was to evaluate the microbiological contamination by Pseudomonas aeruginosa in the water system of the University Hospital “G. Martino” in Messina over a period of nine years, in order to a) clarify possible relationship between the presence of aerators and contamination, b) to highlight the presence of a yearly variation and c) to verify the statistical difference between microbiological contamination of taps with and without filters.

Materials and

Methods

We carried out a retrospective study for nine year through the collection of water samples that were analysed for total bacteria count and Pseudomonas aeruginosa. The differences between the results recorded over the nine-year study period were evaluated using variance analysis. P values of &lt; 0.05 were considered statistically significant. Software R was used for statistical assessment.

Results

We analysed a total of 6168 samples with a positive rate of 9.31% and a decreasing trend over the nine years to a value of 2.44% (p &lt; 0.001), due to the elimination of the aerators of taps without filters and also to the introduction of filters in taps of high-risk wards and surgical rooms. We found statistical difference between taps with or without filter (p &lt; 0.001) and a higher positive rate during the summer season compared to the other months. Also, an increase of the positivity rate was detected in some year due to the lack of monthly replacement of the filter.

Conclusions

These results reveal a high level of contamination of taps by opportunistic bacteria with severe implications especially for high-risk settings and therefore, the need to improve the management of these devices.

Key messages

Particular attention must be reserved to the water distribution systems in hospitals in order to prevent the spread of healthcare associated infections. The continued application and strengthening of guidelines and procedures is essential to limit the spread of multidrug resistant pathogens.

Pregnant women and risk factors: a cross-sectional study

Background

Many investigations have shown the important role played by risk factors such as tobacco and alcohol in the development of congenital anomalies.

Methods

Through the administration of an hoc questionnaire, we evaluated the attitude towards smoking and alcohol of a sample of 200 pregnant women at the University Hospital of Messina. The questionnaire was structured to collect information about socio-demographic characteristics, type of gynaecological assistance and their lifestyles (smoking and alcohol). Statistical analysis was performed using version 10 of StatSoftVR software.

Results

14% of the women continued to smoke despite pregnancy; the majority of these were young adults, divorced, employed and with a high educational level. Correlating the smoking habit with the socio-demographic characteristics of the studied women, we found a statistically significant difference for the marital status, with a higher number of smokers among the single women (p &lt; 0.05).Moreover, we found a statistically significant difference also for the profession with a higher number of smokers in the worker women (p &lt; 0.05). About the drinking habit, the 4.3% declared to be moderate drinkers (occasional use of alcohol equal to 2-3 glasses a week) despite pregnancy, the 34.4% stated they do not drink alcohol during pregnancy and the 56% stated do not usually drink alcohol. Particularly, about the drinkers' socio-demographic characteristics, the 50% of them were 24-25 years old and the 75% were married. About the type of alcoholic beverages consumed, 86% stated they usually drink bier during the weekend.

Conclusions

Our study shows that the awareness of the women about the importance of these risk factors is still rather poor. In order to improve the awareness of pregnant women on the importance of avoiding these risk factors and prevent CAs, health education campaigns at various levels surely represent the public health cornerstone.

Key messages

In our sample 14% of the pregnant women continued to smoke and 4.3% to drink despite pregnancy and they generally were young or young adults and with a high educational level. Our results highlight the importance of continuous health education about the risk to smoke and drink during pregnancy.

Risk perception, knowledge, prevention, information sources and efficacy beliefs related to Covid-19

Background

Sars-Cov-2 is one of the latest examples of an emerging infectious disease challenging the world and it is the third case, in just two decades, of “spillover”. In light of the recent outbreak (Italy is in 2nd position), it is important to evaluate people risk perception and to support the Health Authority with effective communicative actions to avoid the spread of “infodemia”/alarmism. The aim of this study is a) to study levels of perceived threat, risk perception, severity and comparative vulnerability b) to compare risk perception with other communicable/not communicable diseases; c) provide information to increase awareness/ knowledge of the disease.

Methods

We performed an Italian multicentre study from 11 February 2020 and it is still in progress. The subjects in study (general population, HCWs and university students) were enrolled through the administration of a standardized questionnaire based on Health Belief Model through CAPI and CAWI methods. The summary and inferential statistical analyses will be carried out using the R software.

Results

We enrolled 2495 people from 11 February until 4 March 2020. All the respondents had heard of COVID19. Only 2% didn't know any symptoms and 3% answered to all the questions correctly (mean knowledge score of 13). 48% thought that he/she could acquired COVID 19 in the next 12 months and 70% stated that their concern of the disease was high(score5). Perceived capability to avoid it was rated as good/very good by 62%. The correct mask use (WHO) was reported by 64% of the sample and 47% stated all preventive actions (2% no one). Only 22% of the sample stated all actions to be taken in case of suspected acquisition of COVID19.

Conclusions

Italy is facing an epidemic that could have the potential to affect the entire national health system. It's so important to implement public health activities and surveillance systems in order to limit the spread of the disease and bad/disinformation.

Key messages

This study is the first to report on public perception of Sars-Cov-2 in all the Italy. The results indicated that the Italian population is aware of the outbreak and it is concerned about their risk. On the other hand, only half of the sample is aware about all preventive actions and not everybody knows all procedures to be taken in case of COVID 19 suspect.

Nine years of microbiological air monitoring in the operating theatres of a university hospital in Southern Italy

INTRODUCTION

Surgical site infections are among the most frequent Health Care Associated Infections with severe impact on mortality and high economic costs; the role of air microbiological contamination in surgical site infections was amply discussed in the scientific literature, highlighting differences in air contamination rates between different ventilation systems, number of people present and door opening rates.

MATERIAL AND METHODS

The aim of our study was to monitor the presence of bacterial air contamination in operating theaters and its relationship with number of people and type of airflow over a period of nine years (January 2010-November 2018) at Messina's University Hospital. The Rho of Spearman test was used to evaluate differences in microbial contamination between empty and working theaters. The impact of the number of people on colony-forming unit values was assessed by performing a stepwise multiple regression analysis. The differences between the results recorded over the nine-year study period were evaluated using the variance analysis. Software R was used for the statistical assessment.

RESULTS

Air samples were taken in each operating theater over nine years. A total of 1,425 samples were collected with a positivity rate of 37.3%. The median bacterial contamination rate was 30 cfu/m3 in empty theaters, while this rate was significantly higher (P < 0.001) in working theaters, where it reached 85 cfu/m3. A statistically significant difference was identified between laminar and turbulent airflow systems, with higher bacterial contamination rates with the latter (p<0.001); in these cases, the value of bacterial contamination (microbial count) was higher in the presence of a higher number of individuals in the operating theater (p<0.001).

CONCLUSION

Our study demonstrates the complexity of the Operating Theatres environment, in which a good ventilation system is, indeed, only one prerequisite for clean air, but other factors, such as the behavior of healthcare professionals and environmental conditions, can influenced the bacterial count.

Perception of rubella risk in pregnancy: an epidemiological survey on a sample of pregnant women

BACKGROUND

Rubella is a common exanthematous viral disease all over the world. The disease can be prevented by administering a safe and effective vaccine, and in Italy it is subject to reporting obligations. A national plan for the elimination of measles and congenital rubella (in Italian "PNEMoRC") was approved in 2003 and updated in 2010. This plan originally aimed at reducing the susceptible target population (women in fertile age, 15-49 years old) to below 5% and at eliminating the congenital form of rubella by 2015, a goal which has not been achieved yet.

STUDY DESIGN

Our research work was focused on a convenience sample of pregnant women attending the antenatal classes at the two main hospitals in Messina, Sicily (Italy).

METHODS

After we obtained an informed consent, we administered to 200 Italian and foreign pregnant women an anonymous questionnaire reporting socio-demographic characteristics, type of gynaecological assistance and information received about Rubella serological statu.

RESULTS

The mean age was 30.6 years ± 5.45. The majority of these women were married, at work and with a high educational level. Most of them (75.3%) reported to be assisted by a private gynaecologist, while only 24.7% used a public facility. A remarkable percentage (62.8%) of these women reported to be serologically negative at the anti-rubella antibodies test, but, only 7.5% of them reported to have passed the anti-rubella antibody test before the conception.

CONCLUSION

Our results clearly show that we are still far from achieving the elimination of rubella risk in pregnancy. We are facing a cultural gap perhaps also due to a generalized loss of "historical memory" about the impact that infectious diseases have had in the past in terms of mortality and morbidity. In fact, alongside the considerable drop in vaccination coverage in the recent years, our research also reveals a reduced focus on pre-conceptional testing and limited awareness of associated risks. Furthermore, we correlated the serological status with the sociodemographic characteristics of these women and found a statistically significant correlation with their age and their educational level (P<0.05). A lot still needs to be done to improve the situation; in particular, better education at various levels could considerably increase the awareness among women about this relevant public health issue.

Evaluation of Vaccination Coverages in the Health Care Workers of a University Hospital in Southern Italy

INTRODUCTION

An adequate immunization of the health care workers is essential for infection prevention and control, to avoid consequences not only for them, but for all patients that the health care workers could infect causing serious damage and / or death. Unfortunately, to date, despite the presence of international and national guidelines (Law Decree 119/2017), the vaccination coverage was low, also because of the "vaccine hesitancy" spread among the same health care workers. In light of the above, the aim of our study was to investigate the vaccination coverage of healthcare workers of all the operational units present in our hospital and to evaluate differences between sex, age, professional profile and area of work.

MATERIALS AND METHODS

A study was conducted from March to June 2018 to investigate the vaccination coverage of healthcare workers at the University hospital "G. Martino" of Messina; data were collected using a self-completion questionnaire based on Attachment 3 of Ministerial Circular 25233 of 18 August 2017. We verified any possible association between physicians and pediatricians and between age classes by the chi square method. Also, a logistic regression was used for each vaccination, considering the vaccination as the variable and the following covariates: type of operative unit, sex, age and area) in order to predict the probability of vaccination.

RESULTS

We analyzed a sample of 822 health care workers (324 males and 498 females with an age of 49.5 ± 10.5 SD). The sample was made up of physicians (36%), nurses (21%) and other professional categories (43%). Analyzing the data we obtained vaccination coverages lower than the target required to guarantee "herd immunity"; higher vaccination coverages were found for females, physicians and the clinical area and - for influenza vaccination - in the older age groups and - for all the other vaccinations - in the younger groups.

CONCLUSION

Data analysis revealed a lax attitude towards vaccinations by health care workers and the need for measures aimed at increasing vaccination their coverage to prevent them from becoming a source of dangerous outbreaks.

An observational study of university students of healthcare area: knowledge, attitudes and behaviour towards vaccinations

INTRODUCTION

Despite vaccines are the most successful public health interventions for prevention of infectious diseases "vaccine hesitancy" spreads today across the world. Despite attitudes of future generations of HCWs is fundamental, these aren't much analysed in the literature. The aim of our research was a) to evaluate attitudes and behaviours reported towards vaccinations among a sample of university students in the health area, b) to know their vaccination status and intention to get vaccines and c) investigate their propensity to vaccinate (who and with which vaccines).

MATERIALS AND METHODS

We evaluated a sample of university students of the health area of University of Messina through an anonymous face to face questionnaires based on HProimmune survey appropriately modified, analysing presence of statistical difference between gender. All analyses were carried out using EPI INFO software.

RESULTS

Our study showed a general lack of confidence and insecurity towards vaccination by future HCWs and absent perception of the risk of acquire a vaccine preventable disease as they also demonstrate low vaccination coverage in our sample. Their opinion about awareness of recommended vaccines for HCWs also was low, however, they thought that vaccinations should be a prerequisite for healthcare professionals to work in healthcare area. Also, we observed that 96% of respondents would recommend vaccinations to their patients, with a greater propensity of women.

CONCLUSIONS

The motivations of vaccine hesitancy are many and maybe other studies would help policymakers and stake-holders to shape programs to improve vaccination coverage among students and HCWs.

The evolution of vaccines for early childhood: the MMRV

Measles, mumps, rubella and varicella vaccines have greatly reduced the incidence of these four childhood diseases, which in the past caused a considerable burden of morbidity and lethality to the population. Vaccines against MMR, varicella and a tetravalent MMRV vaccine are currently available on the market to provide immunization against measles-mumps-rubella and varicella. A recently passed Italian Law (L 119/2017) on vaccinations increased the number of free of charge but compulsory vaccinations from four to ten, including MMR and varicella, as a requirement for admission to nursery schools and kindergartens; fines may be levied for non compliance, in the attempt to increase vaccination coverage. The Italian National Immunization Program 2017-19 allows immunization to be administered either by: the trivalent anti-measles-mumps-rubella plus the monovalent anti-varicella vaccine, administered in different anatomic sites at the same session, or by a quadrivalent MMRV combined vaccine.

Knowledge, experiences, and attitudes toward Mantoux test among medical and health professional students in Italy: a cross-sectional study

BACKGROUND

The World Health Organization's Action Framework for tuberculosis elimination in low-tuberculosis incidence countries includes the screening for active and latent tuberculosis in selected high-risk groups, including health care workers. In this context, medical and health profession students, exposed to nosocomial tuberculosis transmission during training and clinical rotations, are target populations for tuberculosis screening. No updated data are available on tuberculosis screening practice and knowledge of medical and health profession students in Italy.

METHODS

Within the activities Italian Study Group on Hospital Hygiene of the Italian Society of Hygiene, Preventive Medicine and Public Health, we carried out a multicentre cross-sectional study to assess knowledge, attitude and practices on tuberculosis prevention and control among Medical, Dentistry, Nursing and other health professions' students. Students were enrolled in the study on a voluntary basis and were administered a previously piloted structured questionnaire. Logistic regression models were applied to explore knowledge on tuberculosis prevention by selected socio-demographic variables and University-based tuberculosis prevention practice.

RESULTS

Students of seventeen Universities across Italy participated in the study, and 58.2% of them received compulsory tuberculin skin test either at enrollment or while attending clinical practice. A total of 5,209 students filled the questionnaire. 37.7% were medicine and dentistry students (Group 1), 44.9% were nursing students (Group 2) and 17.4% were other health professions' students (Group 3). Age and gender had different distributions by groups, as well as knowledge and practice on tuberculin skin test. 84.4% of the study population (95% CI = 83.3-85.3) was aware of the existence of the tuberculin skin test, 74.4% (95% CI = 73.2-75.6) knew what is the first-level screening test for latent tuberculosis and only 22.5% (95% CI = 21.4-23.6) knew how to proceed after a positive tuberculin skin test result. Overall, knowledge on tuberculosis prevention was higher in Group 2 and lower Group 3, as compared to Group 1.

CONCLUSION

In Italy, the knowledge on tuberculosis screening among University students is generally good. To reduce some of the criticalities found among the different study courses, it would be appropriate to harmonize both the regulations on tuberculosis screening practices for admission to University courses, and the educational activities on the topic of tuberculosis, to be extended to all workers involved in health care setting.

Effects of aerators, filters and chlorination on contamination of water samples: a nine years study in a Southern University Hospital

OBJECTIVES

The aim of our study was to evaluate the microbiological contamination by Pseudomonas aeruginosa in the water system of the University Hospital "G. Martino" in Messina over a period of nine years, in order to a) clarify possible relationship between the presence of aerators and contamination, b) to highlight the presence of a yearly variation and c) to verify the statistical difference between microbiological contamination of taps with and without filters.

MATERIAL AND METHODS

We carried out our study between January 2010 and December 2018 through the collection of water samples that were analysed for total bacteria count and Pseudomonas aeruginosa. The differences between the results recorded over the nine-year study period were evaluated using variance analysis. P values of <0.05 were considered statistically significant. Software R was used for statistical assessment.

RESULTS

We analysed a total of 6168 samples with a positive rate of 9.31% and a decreasing trend over the years to a value of 2.44% (p<0.001), due to the elimination of the aerators of taps without filters and also to the introduction of filters in taps of high-risk wards and surgical rooms. We found statistical difference between taps with or without filter (p<0.001) and a higher positive rate during the summer season compared to the other months.

CONCLUSIONS

These results reveal a high level of contamination of taps by opportunistic bacteria with severe implications especially for high-risk settings and therefore, the need to improve the management of these devices.

Drug-resistant bacteria on hands of healthcare workers and in the patient area: an environmental survey in Southern Italy's hospital

OBJECTIVE

Drug-resistant bacteria on hands of healthcare workers and in the patient area: an environmental survey in Southern Italy's hospital.

METHODS

The study was conducted from June 2017 to May 2018 using contact slides for surfaces and active sampling for air. We used automated biochemical methods to identify microorganisms; antibiograms were performed in compliance with the EUCAST expert rules.

RESULTS

We analyzed 3,760 samples, 16.17% were found positive and 34 % of these were antimicrobial-resistant. On analyzing the isolated Staphylococci, 39% were multidrug-resistant and 5% extensively drug-resistant. A 30% of the Enterococcus faecalis isolates were resistant to gentamycin and vancomycin. We found Klebsiella pneumoniae isolates resistant to ceftriaxone, cefoxitin, mecillinam and imipenem. A 7% and 8% of the Acinetobacter baumannii and Pseudomonas aeruginosa isolates, respectively, were resistant to gentamicin, imipenem, and ceftazidime.

CONCLUSIONS

These findings are in line with the international literature, confirming that antimicrobial resistance is also steadily growing in Italy with rates varied for the different pathogens.

"Clean care is safer care": correct handwashing in the prevention of healthcare associated infections

BACKGROUND

In 2005, WHO developed the campaign "Clean care is safer care", aiming at the reduction of Healthcare Associated Infections (HCAI) through the worldwide promotion of appropriate hand hygiene practices. Adherence to these practices presently ranges from 5 to 81% (average 40%).

METHODS

Aim of the study was the evaluation of healthcare workers (HCWs) adherence to the application of WHO guidelines on the hand hygiene and the possible impact on HCAI reduction. First, some wards at highest HCAI risk were identified. Then, direct observational survey was conducted to evaluate the behaviour of the different HCW categories.

RESULTS

Six-hundred-twenty-eight HCWs were observed: 519 nurses (68 in training), 109 physicians (63 in training). Survey analysis highlighted that compliance with handwashing was higher in post care practices (59.6%) than before (55.1%). Some HCWs performed handwashing in both cases. Only in 30.6% of cases HCWs observed the handwashing technique suggested by the guidelines. In 70.4% they wore gloves during procedures in which it was possible to have contact with potentially infectious material, but they did not change them before caring for a new patient in 64% of cases.

CONCLUSIONS

The survey confirms the international data, showing a low compliance with hand hygiene practices by the HCWs and the need to promote a correct handwashing based on respect of the international guidelines.

An evaluation of attitude toward vaccines among healthcare workers of a University Hospital in Southern Italy

BACKGROUND

Vaccination is an effective and safe health technology. Despite this vaccine coverage falls short of national and international targets. Study design. The aim of the study was to evaluate the views of medical staff at Messina University Hospital regarding vaccinations, their current and future vaccination status and whether they recommend it to their patients.

METHODS

The study was conducted from April 2016 to March 2017 by an anonymous face-to-face questionnaire submitted to HCWs.

RESULTS

A general lack of confidence and insecurity about vaccination was shown by a substantial proportion of physicians analyzed while pediatricians showed a positive attitude to vaccines. However, many physicians had not been immunized with the recommended vaccines for HCWs and therefore represent a potential source of infection for both patients and the general population.

CONCLUSIONS

Despite the evidence of the effectiveness and safety of vaccines, compliance by HCWs remains very low for a variety of reasons. A range of measures are therefore needed to ensure their use, not only by the general population, but also by doctors who should be their major promoters.

Blood-Brain Barrier in a Haemophilus influenzae Type a In Vitro Infection: Role of Adenosine Receptors A2A and A2B

The blood-brain barrier (BBB) is mainly made up of tightly connected microvascular endothelial cells (BMECs), surrounded by pericytes (BMPCs) which regulate BBB tightness by providing soluble factors that control endothelial proliferation. Haemophilus influenzae type a (Hia) is able to reach the BBB, crossing it, thus causing meningitis. In this study, by using an in vitro model of BBB, performed with human BMECs and human BMPCs in co-culture, we demonstrated that, after Hia infection, the number of hBMPCs decreased whereas the number of hBMECs increased in comparison with non-infected cells. SEM and TEM images showed that Hia was able to enter hBMECs and reduce TEER and VE-cadherin expression. When the cells were infected in presence of SCH58261 and PSB603 but not DPCPX, an increase in TEER values was observed thus demonstrating that A_2A and A_2B adenosine receptors play a key role in BBB dysfunction. These results were confirmed by the use of adenosine receptor agonists CGS21680, CCPA, and NECA. In infected co-cultures cAMP and VEGF increased and TEER reduction was counter-balanced by VEGF-R1 or VEGF-R2 antibodies. Moreover, the phosphorylated CREB and Rho-A significantly increased in infected hBMECs and hBMPCs and the presence of SCH58261 and PSB603 significantly abrogated the phosphorylation. In conclusion, this study demonstrated that the infection stimulated A_2A and A_2B adenosine receptors in hBMECs and hBMPCs thus inducing the pericytes to release large amounts of VEGF. The latter could be responsible for both, pericyte detachment and endothelial cell proliferation, thus provoking BBB impairment.

Management of two influenza vaccination campaign in health care workers of a university hospital in the south Italy

BACKGROUND

In Europe, flu remains one of the major public health problems. Healthcare workers (HCWs) are a category at high-risk of contracting the infection and infecting their patients; consequently, for this category, vaccination is highly recommended. Unfortuntely, coverage levels remain insufficient with rates ranging between 4 and 40.

STUDY DESIGN

The purpose of our work was to evaluate the adherence of HCWs to the influenza vaccination and to carry out a combination of educational and motivational interventions in order to increase the rate of adherence to the vaccination in this workers' category.

METHODS

We conducted two different influenza vaccination campaigns, 2014-2015 and 2015-2016. The study was divided in two steps. In the first, preliminary step, an anonymous questionnaire was administered to HCWs containing a set of questions in order to gain information about the number of subjects willing to undergo the vaccination and the reasons that led others toits rejection. In the second step, vaccination campaigns were carried out preparing an appropriate vaccination calendar that was communicated to all interested Units and vaccination points located in various wards.

RESULTS

We found a slightly improved compliance trend, from an average of 2.3% in the previous years to 3.3% in 2014 and 7.4% in 2015.

CONCLUSIONS

Despite the observed increase, the adherence remains very low. We found that the main causes of this result are the fear of adverse effects, the negligence and indolence of the same workers and a lack of risk perception of contracting the disease and transmitting it to patients. Our work stressed the importance of offering correct information and of meeting the needs of HCWs, often unable to leave their ward for the excess workload. This could be, in future years, one of the possible solutions to increase vaccination adherence.

Alterations of the vaginal microbiota in the third trimester of pregnancy and pPROM

OBJECTIVE

Preterm premature rupture of membranes (pPROM) is a significant issue in obstetric practice. One of the risk factors for pPROM are vaginal infections in the third trimester of pregnancy.

PATIENTS AND METHODS

We performed an observational study on 600 pregnant women, analyzing the lactobacillary grade (LBG) and the presence of any pathogenic bacteria and/or Candida at weeks 28 and 32 of pregnancy and recording any pPROM events at delivery. At week 28, in the case of vaginal infection, the patients were treated for 6 days with a topical association of metronidazole+clotrimazole.

RESULTS

At week 28 of pregnancy 54.2% of women had vaginal infection (32.6% bacterial vaginitis, 33.8% candidiasis and 32.4% mixed infection) and/or abnormal vaginal microbiota (67.4% LBG 2a/2b, 32.6% LBG 3). The total number of pPROM was 8 out of 600 (1.3%). The treatment of vaginal infection at week 28 with the topical association of metronidazole+clotrimazole, led to both the eradication of vaginal infections and the restoration of the vaginal microbiota in 72% of the cases, bringing the level of risk of pPROM similar to that of women without vaginal infection at week 28. In addition, the results showed that women with vaginal infections and/or alteration of vaginal microbiota at week 32 of pregnancy had a higher prevalence of pPROM in comparison to the women without vaginal infection at week 32 (p<0.001).

CONCLUSIONS

This observational study showed the high prevalence of vaginal infections in the third trimester of pregnancy and its association with pPROM. Furthermore, data suggested the possible benefits of the topical treatment with metronidazole+clotrimazole in pregnancy to eradicate infections, restore the normal microbiota and reduce the risk of pPROM.

Iatrogenic nocturnal eneuresis – an overlooked side effect of anti histamines?

Nocturnal enuresis is a common disorder in childhood, but its pathophysiological mechanisms have not been fully elucidated. Iatrogenic nocturnal enuresis has been described following treatment with several psychotropic medications. Herein, we describe a 6-year-old child who experienced nocturnal enuresis during treatment with the antihistamine cetirizine. Drug rechallenge was positive. Several neurotransmitters are implicated in the pathogenesis of nocturnal enuresis, including noradrenaline, serotonin and dopamine. Antihistamine treatment may provoke functional imbalance of these pathways resulting in incontinence.

Electrocatalytic conversion of CO2 to produce solar fuels in electrolyte or electrolyte-less configurations of PEC cells

The electrocatalytic reduction of CO2 is studied on a series of electrodes (based on Cu, Co, Fe and Pt metal nanoparticles deposited on carbon nanotubes or carbon black and then placed at the interface between a Nafion membrane and a gas-diffusion-layer electrode) on two types of cells: one operating in the presence of a liquid bulk electrolyte and the other in the absence of the electrolyte (electrolyte-less conditions). The results evidence how the latter conditions allow productivity of about one order of magnitude higher and how to change the type of products formed. Under electrolyte-less conditions, the formation of >C2 products such as acetone and isopropanol is observed, but not in liquid-phase cell operations on the same electrodes. The relative order of productivity in CO2 electrocatalytic reduction in the series of electrodes investigated is also different between the two types of cells. The implications of these results in terms of possible differences in the reaction mechanism are commented on, as well as in terms of the design of photoelectrocatalytic (PEC) solar cells.

Inhibitory activity of cranberry extract on the bacterial adhesiveness in the urine of women: an ex-vivo study

Strains of uropathogenic E. coli are responsible for approximately 90% of community-acquired, uncomplicated cystitis, and fimbriae represent the adhesive factors enabling E. coli to be anchored to uroepithelial cells in the first step of the infectious process. Recently, a few studies have shown that a correlation between the consumption of cranberry (Vaccinium macrocarpon) and prevention of UTI is related to the ability of proanthocyanidins to reduce the bacterial adhesion to uroepithelial cells. In this study we evaluate the inhibitory activity of urine of healthy women treated with tablets containing cranberry extract on the adhesiveness of E. coli to uroepithelial human cells. Two groups of 12 female volunteers each, aged between 18 and 65 years, were enrolled, one group with negative history and one group with positive history of recurrent cystitis. Subjects were treated with the active product or placebo in a random, cross-over, double-blinded sequence for one week in each of the two treatment sequences. Urine samples were collected at the beginning and the end of each study period. Tests of bacterial adhesiveness were performed with two strains of E. coli (ATCC 25922 and ATCC 35218) on HT1376 human bladder carcinoma cells. Significant reductions of bacterial adhesiveness were observed in women who received cranberry extract (-50.9%; p less than 0.0001), regardless of their medical history and the treatment period in the cross-over sequence. No changes were observed with placebo (-0.29%; n.s.). This ex-vivo study showed that the assumption of cranberry extract in suitable amounts can have an anti-adhesive activity on uropathogenic E. coli.

In Vitro Activity of Cefditoren versus other Antibiotics against S. Pneumoniae Clinical Strains Isolated in Italy

Over the last twenty years there has been an alarming increase in isolation of Streptococcus pneumoniae strains with a reduced susceptibility not only to penicillin, but also to other betalactams and macrolides. This phenomenon justifies the great interest in new antibiotics. Cefditoren, a new aminothiazolyl oral cephalosporin, recently commercialized in Italy, is characterized by an extended activity against penicillin-resistant S. pneumoniae. The aim of this study is to evaluate the incidence of the resistance/susceptibility to various antibiotics in 1000 strains of S. pneumoniae (678 SPSS, 219 SPPI and 103 SPPR), clinically isolated during 2009. The data obtained by our in vitro study show that cefditoren is the most active agent against S. pneumoniae. In fact, the MIC90 values of 0.5 fig/ml obtained could be particularly significant in terms of therapeutic predictivity.

In vitro evaluation of the synergistic activity of neomycin-polymyxin B association against pathogens responsible for otitis externa

The most recent guidelines recommend, for otitis externa antibiotic therapy, the use of topical formulations in that they are very safe, have a quicker effect and do not induce bacterial resistance compared to systemic therapy. The choice of the class of antibiotics in empiric therapy of otitis externa must take into consideration the polymicrobic nature of the infection that includes both bacteria (Grampositive and Gram-negative) and mycetes. For this reason, in this study we evaluated the synergic activity of neomycin in association with polymyxin B against the pathogens commonly responsible for otitis externa, compared to that of a single antibiotic (ciprofloxacin). The polymyxinB/neomycin association shows clear synergic effects with values of both Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) reduced by 3-4 times with respect to the single antibiotic; and in P. aeruginosa the synergistic effect of the neomycin/polymyxin B association with respect to neomycin was more evident (5-6 times), with an intrinsic in vitro activity constantly higher than that of ciprofloxacin alone or in association with hydrocortisone. From the analysis of the data obtained in vitro, we can conclude that the possibility of using a topical formulation containing a synergistic association of antibiotics, such as neomycin-polymyxin B, in such a way as to obtain the maximum effect in the minimum time with an increase in the spectrum of action of non-bacterial pathogens, is an optimal choice for the clinician for the empiric therapy of otitis externa.

Cell cycle control and beyond: emerging roles for the retinoblastoma gene family

Rb family proteins (pRb/p105, Rb2/p130 and p107) play a key role in cell cycle control and are worthily involved in transcription repression and tumor suppression. The mechanisms of transcriptional activation and repression by the Rb gene family has been extensively investigated: pRb, pRb2/p130 and p107 interact with different E2F family factors and can inhibit E2F responsive promoters, interfering with progression of cell cycle, gene transcription, initiation of apoptotic process and cell differentiation. Recent studies have indicated that Rb and Rb2/p130 may be involved in cellular response to DNA damage events, by influencing the transcription of factors involved in DNA repair pathways. In particular, evidences suggest that Rb loss and target gene deregulation impacts on the repair of UV-induced pyrimidine pyrimidone photoproducts (6-4 PP) by regulating the expression of several DNA damage factors involved in UV DNA damage repair processes, including proliferating cell nuclear antigen. Ongoing studies are focused on the mechanisms by which Rb family genes drive cell cycle exit following DNA damage induction, and how Rb gene family's interaction with chromatin remodeling factors can influence DNA repair dynamics.

[Motivation, expectations, realization: from education to work]

This paper presents the outcomes of a research oriented to exploration and description of the motivations and expectations that concur to assumption af an active and intentional role from students engagaged for achievement of knowledges, skills and highly qualitative consistent attitudes with practice of nursing service.

Cerebellar hemispheric activation ipsilateral to the paretic hand correlates with functional recovery after stroke

An experimental lesion in the primary motor or sensory cortices in monkeys leads to functional reorganization in areas surrounding the lesion or in contralateral homologous regions. In humans, task-dependent brain activation after motor stroke seems to be multifocal and bilateral. Although many active structures are seen after stroke, their roles are unclear. For instance, the uninjured primary motor cortex may play a significant role in recovery or may be associated with mirror movements. Other motor areas, particularly those outside the affected middle cerebral artery distribution, have also been thought to play such a role, including the medial pre-motor areas and both cerebellar hemispheres. The lateral pre-motor areas might also contribute but the demarcation of primary motor and pre-motor cortices is not trivial. It is not known from existing studies how brain activation relates to behavioural change over the time course of recovery. We used functional MRI (fMRI) to study 12 patients longitudinally over the first 6 months of stroke recovery. All subjects had acute stroke causing unilateral arm weakness and had some ability to move the impaired hand within 1 month. Each patient had both motor testing and fMRI during finger and wrist movements at four points during the observed period. Six of these patients showed good motor recovery, whereas the other six did not. The imaging results support a role for the cerebellum in mediating functional recovery from stroke. The data suggest that patients with good recovery have clear changes in the activation of the cerebellar hemisphere opposite the injured corticospinal tract. Patients with poor recovery do not show such changes in cerebellar activation. No other brain region had a significant correlation with recovery. Interestingly, activation in the cerebellum ipsilateral to the injury increases transiently after stroke, independently of the success of recovery. The present work suggests a possible link between cerebellar activation and behavioural recovery from hand weakness from stroke. The underlying mechanism is not known, but it could relate to haemodynamic changes such as diaschisis or to the postulated role of the cerebellum in motor skill learning.

Inactivating mutations in an SH2 domain-encoding gene in X-linked lymphoproliferative syndrome

X-linked lymphoproliferative syndrome (XLP) is an inherited immunodeficiency characterized by increased susceptibility to Epstein-Barr virus (EBV). In affected males, primary EBV infection leads to the uncontrolled proliferation of virus-containing B cells and reactive cytotoxic T cells, often culminating in the development of high-grade lymphoma. The XLP gene has been mapped to chromosome band Xq25 through linkage analysis and the discovery of patients harboring large constitutional genomic deletions. We describe here the presence of small deletions and intragenic mutations that specifically disrupt a gene named DSHP in 6 of 10 unrelated patients with XLP. This gene encodes a predicted protein of 128 amino acids composing a single SH2 domain with extensive homology to the SH2 domain of SHIP, an inositol polyphosphate 5-phosphatase that functions as a negative regulator of lymphocyte activation. DSHP is expressed in transformed T cell lines and is induced following in vitro activation of peripheral blood T lymphocytes. Expression of DSHP is restricted in vivo to lymphoid tissues, and RNA in situ hybridization demonstrates DSHP expression in activated T and B cell regions of reactive lymph nodes and in both T and B cell neoplasms. These observations confirm the identity of DSHP as the gene responsible for XLP, and suggest a role in the regulation of lymphocyte activation and proliferation. Induction of DSHP may sustain the immune response by interfering with SHIP-mediated inhibition of lymphocyte activation, while its inactivation in XLP patients results in a selective immunodeficiency to EBV.

Antibodies against 1D, a recombinant 64-kDa membrane protein, are associated with ophthalmopathy in patients with thyroid autoimmunity

We have tested for serum antibodies reactive with 1D, a recombinant 65-kDa human thyroid protein which is also expressed in eye muscle, in patients with thyroid autoimmunity and ophthalmopathy by immunofluorescence and SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. We also measured antibodies to a 64-kDa pig eye muscle membrane protein which is identified by SDS-PAGE and Western blotting, correlating the two reactivities. While antibodies to 1D, expressed in Chinese hamster ovary (CHO) cell membrane, were detected in approximately 40% of patients with ophthalmopathy, in both tests the greatest prevalence, by immunofluorescence, 73%, was demonstrated in patients with Graves' hyperthyroidism without clinically evident eye disease, although only 50% of these patients were positive in immunoblotting. When the two tests for anti-1D antibodies were compared, immunofluorescence appeared to be the more specific and immunoblotting appeared to be the more sensitive. The greatest prevalence of antibodies reactive with a 64-kDa pig eye muscle protein, 71%, was in patients with TAO of less than 1 year duration; tests were positive in 49% of patients with more chronic ophthalmopathy and in 50% of patients with Graves' hyperthyroidism without evident eye disease. Antibodies reactive with 1D were detected in 17% of normals by immunofluorescence and 24% by immunoblots, while antibodies reactive with the 64-kDa pig eye muscle protein were detected in only 10% of the normal subjects tested. Lesser prevalences of antibodies to the two 64-kDa proteins in patients with established eye disease suggest that such antibodies may be an early abnormality in patients with Graves' hyperthyroidism who are predisposed to develop ophthalmopathy. Although the association was not close, reactivity against 1D by immunoblotting, but not immunofluorescence, was significantly correlated with reactivity to a 64-kDa eye muscle membrane protein by immunoblotting. On the other hand, when sera containing antibodies reactive with both 1D and the 64-kDa eye muscle protein were incubated with CHO (1D) cell membrane, reactivity against 1D was absorbed while that against the eye muscle protein was not. The precise relationship between the two 64-kDa proteins can only be clarified by cloning the 64-kDa protein from an eye muscle expression library and comparing the sequences with those of 1D.

Serum antibody production to botulinum A toxin

PURPOSE

Conflicting data have been reported regarding development of serum antibodies to botulinum A toxin. The purpose of this study is to determine conclusively whether antibody production to this toxin occurs in humans, and, if so, to determine its relationship, if any, to length of treatment, total cumulative dose, and clinical response to treatment.

METHODS

Sixty-five sera samples from 42 adults treated with botulinum A toxin for essential blepharospasm, hemifacial spasm, or spasmodic torticollis were analyzed via a sphere-linked immunodiagnostic assay for antibody production. Results were plotted against length of treatment, number of injections, cumulative dose, and treatment effect produced.

RESULTS

Twenty-four (57%) of the 42 patients produced antibodies in all three diagnostic groups. No significant differences were found between antibody producers and nonproducers with respect to age (P = 0.216), length of treatment (P = 0.586), number of injections (P = 0.619), or total cumulative dose (P = 0.286). Within the antibody-producing group, there was no significant correlation between amount of antibody and length of treatment (P = 0.081), number of injections (P = 0.134), or cumulative dose (P = 0.250). The presence of demonstrable antibodies in serum did not affect the clinical responsiveness to injection.

CONCLUSION

Antibody production is present in a majority of patients treated with botulinum A toxin. The sphere-linked immunodiagnostic assay is a reliable and reproducible method for detecting and quantifying these antibodies. When antibody production occurs, it is likely due to variations in individual immune responsiveness and appears to have no direct effect on the patient's clinical response to treatment.

Pathogenesis of thyroid-associated ophthalmopathy: an autoimmune disorder of the eye muscle associated with Graves' hyperthyroidism and Hashimoto's thyroiditis

Thyroid-associated ophthalmopathy, the progressive eye disorder which occurs frequently in patients with Graves' hyperthyroidism and, occasionally, in those with Hashimoto's thyroiditis, may be a two-stage disorder of the eye muscle. In the first stage, which may occur in the great majority of patients with Graves' hyperthyroidism and in an unknown, but probably small, proportion of those with Hashimoto's thyroiditis, antibodies and CD4+ (helper) T lymphocytes reactive with eye muscle and thyroid shared antigens, of which 64-kDa membrane proteins are good candidates, may initiate a mild eye muscle inflammation, manifested as eye muscle swelling on orbital imaging. The second stage, which occurs in about 25% of patients with Graves' hyperthyroidism and in 2% of those with Hashimoto's thyroiditis, may be due to reactivity of cytotoxic antibodies against eye muscle-specific membrane antigens, one of which at approximately 35 kDa appears a likely candidate, and, possibly, cytotoxic T cells in the context of the appropriate class I MHC molecule. Orbital connective tissue inflammation, which plays an important role in the development of progressive orbital inflammation, is likely to be secondary to the eye muscle reaction. The recent cloning of a 64-kDa thyroid and eye muscle antigen which shares significant homology with the muscle protein tropomodulin and mapping of its antibody-reactive epitopes provide structural information about one candidate eye muscle autoantigen and promise for a more rational approach to the diagnosis and management of this common, progressive eye disorder.

A comparison of apparent mRNA half-life using kinetic labeling techniques vs decay following administration of transcriptional inhibitors

Several different techniques were used to determine the apparent half-lives of immunoglobulin gamma 2b heavy chain and kappa light chain mRNA's in mouse myeloma 4T001 and a mutant derived from 4T001, i.e., mutant I17. The mutant I17 Ig heavy chain mRNA lacks CH1 and has fused CH2 and CH3 domains resulting in a truncated protein. By all four techniques the Ig heavy chain mRNA from mutant I17 displays a half-life that is approximately 70% the half-life of Ig mRNA in 4T001 cells. However, the absolute values of apparent half-life varied by greater than twofold for both lines among several of the techniques employed. The half-life of Ig gamma 2b mRNA in 4T001 cells was found to be 6.4 h by measuring decay following administration of the adenosine analog DRB to block new mRNA synthesis and 5.7 hr by measuring accumulation in an approach to steady-state labeling protocol. In contrast, the observed Ig mRNA half-lives determined by measuring decay following administration of actinomycin D to block new mRNA synthesis, or in a pulse-chase analysis were 2.9 and 3.8 h, respectively. The apparent half-life for Ig kappa light chain mRNA was the same in the 4T001 and I17 lines using any one technique but the value varied depending on the technique from a high value of 5.9 h following DRB to a low value of 2.4 h with actinomycin decay. Approach to steady-state is theoretically the most accurate method to measure mRNA half-life when that value is less than the doubling time of the cells. Pulse-chase analyses are accurate for measuring mRNA half-life when that value is longer than the effective chase period. Measuring preformed message decay following administration of drugs to block new mRNA synthesis is adaptable over a range of half-lives, but the cells must be shown to retain correct RNA metabolism over the time frame of the experiment. Determining a correct half-life for a particular mRNA may not be feasible using only one method and may, in fact, require several different approaches until a consensus value emerges.

Differential mRNA stabilities affect mRNA levels in mutant mouse myeloma cells

A series of mouse myeloma cell lines producing mutant gamma 2b immunoglobin heavy chains, which resemble heavy chain disease proteins, were analyzed for messenger RNA abundance as a function of mRNA alterations. A mutation effectively deleting the gamma 2b-CH1 domain of the mRNA had little or no effect on Ig heavy chain mRNA abundance on half-life (mutant 10.1). A mutation in the gamma 2b-CH2 and CH3 domain, causing premature termination of translation, had more deleterious effects on Ig heavy chain mRNA abundance and half-life (mutant I17). Substitution of the deleted portions of the gamma 2b mRNA with gamma 2a sequences by subclass switching in the cells (mutants K23 and K25) resulted in increased heavy chain abundance and half-life relative to the parent I17. In contrast, kappa light chain mRNA levels and half-lives remain constant among the mutants. The wild-type and mutant cell lines transcribed the Ig heavy chain gamma 2b locus equally when compared with an internal beta-actin standard by transcription run on studies. Therefore, half-life of the Ig heavy chain mRNA seems to be the principal determinant in cytoplasmic mRNA abundance in this system.

Increased half-life of mu immunoglobulin mRNA during mouse B cell development increases its abundancy

When B cells encounter antigen, the cells mature into terminally differentiated plasma cells and the amount of steady-state immunoglobulin (Ig) mu mRNA is increased 23-60-fold over the amount seen in earlier B cell stages. Most of this dramatic increase in Ig gene mRNA accumulation could be due to post-transcriptional regulation. We have treated a series of mouse cell lines fixed at different stages of B cell differentiation with an adenosine nucleotide analog 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) which specifically blocks synthesis of new RNA polymerase II transcripts. The amount of mu heavy chain cytoplasmic RNA, measured by quantitative Northern blot analysis at various times post DRB treatment, is reflective of the transcript's stability. The mu mRNA half-life values observed from the earliest-stage lymphomas (70Z/3 and WEHI-231) are about 1.9-4 hr, whereas the t1/2 of mu mRNA in the hybridomas (Hyb54.3C2 and IdG11) is about 13-17 hr. There is, therefore, a nine-fold maximal increase in half-life of the mu mRNA in the Hyb54.3C2 over that observed in the earliest stage (70Z/3) cells.