Investigations of the immunomodulatory effect of cyanobacterial extracts]

Resulting from the knowledge that cyanobacteria (blue-green algae) are able to produce pharmacologically active substances the aqueous extracts from several cyanobacteria species and strains (Microcystis aeruginosa, Synechocystis aquatilis, Oscillatoria redekei, Anabaena flos-aque, Aphanizomenon flos-aquae, Oscillatoria rubescens, Oscillatoria tenuis) were tested for their immunomodulating activity. Extracts from Oscillatoria redekei 051, Oscillatoria tenuis 01 and Synechocystis aquatilis 428 caused an immunosuppression. They inhibited not only the incorporation of 3H-thymidine into mitogen stimulated lymphocytes but reduced also the number of plaque-forming cells of mice as shown by hemolysis-plaque-assay. Only extracts from Oscillatoria redekei 051 did not show any cytotoxic effects in lymphocyte cytotoxic test. This may be an evidence for a specific action on the proliferation of lymphocytes.     

Involvement of the 12-lipoxygenase pathway of arachidonic acid metabolism in homosynaptic long-term depression of the rat hippocampus

Low-frequency stimulation is associated with long-term depression (LTD) of synaptic efficacy in various brain structures. Like long-term potentiation (LTP), homosynaptic LTD in area CA1 of the hippocampus appears to require NMDA receptor activation, changes in postsynaptic calcium concentration and phospholipase A₂ (PLA₂) activation. Arachidonic acid (AA) is released after the activation of calcium-dependent phospholipases and free AA is rapidly metabolized to a family of bioactive products (the eicosanoids) which are thought to be both intracellular and extracellular messengers. In the present study, we investigated the involvement of the cyclooxygenase and lipoxygenase pathways of AA metabolism in the formation of homosynaptic LTD in the rat hippocampus. Stimulation at 1 Hz for 15 min was used to produce homosynaptic depression in area CA1 of hippocampal slices. LTD induction was partially blocked by bromophenacyl bromide (50–100 μM), a selective PLA₂ inhibitor, and by the a nonselective lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA; 100 μM). In contrast, the specific cyclooxygenase blocker indomethacin (100 μM) did not significantly reduce hippocampal LTD. Since NDGA interferes with LTD formation, we examined whether specific inhibitors of 5- and 12-lipoxygenases were capable of blocking LTD expression. The 12-lipoxygenase inhibitor baicalein at a concentration of 50 μM reduced LTP formation when given in the bath, an effect that was less pronounced with the 5-lipoxygenase inhibitor AA-861. These data suggest that the activation of endogenous PLA₂ and the formation of 12-lipoxygenase metabolites of AA may be important factors controlling the expression of hippocampal LTD.     

COVID-19 and its effects upon orthopaedic surgery: The Trinidad and Tobago experience

The World Health Organisation(WHO) declared coronavirus disease 2019(COVID-19) a pandemic on March 11, 2020. COVID-19 is not the first infectious disease to affect Trinidad and Tobago. The country has faced outbreaks of both Chikungunya and Zika virus in 2014 and 2016 respectively. The viral pandemic is predicted to have a significant impact upon all countries, but the healthcare services in a developing country are especially vulnerable. The Government of Trinidad and Tobago swiftly established a parallel healthcare system to isolate and treat suspected and confirmed cases of COVID-19. Strick ‘lockdown' orders, office closures, social distancing and face mask usage recommendation were implemented following advice from the WHO. This approach has seen Trinidad and Tobago emerge from the second wave of infections, with the most recent Oxford COVID-19 Government Response Tracker report indicating a favourable risk of openness index for the country. The effects of the pandemic on the orthopaedic services in the public and private healthcare systems show significant differences. Constrained by shortages in personal protective equipment and inadequate testing facilities, the public system moved into emergency mode prioritizing the care of urgent and critical cases. Private healthcare driven more by economic considerations, quickly instituted widespread safety measures to ensure that the clinics remained open and elective surgery was not interrupted. Orthopaedic teaching at The University of the West Indies was quickly migrated to an online platform to facilitate both medical students and residents. The Caribbean Association of Orthopedic Surgeons through its frequent virtual meetings provided a forum for continuing education and social interaction amongst colleagues. The pandemic has disrupted our daily routines leading to unparalleled changes to our lives and livelihoods. Many of these changes will remain long after the pandemic is over, permanently transforming the practice of orthopaedics.     

Epidemiological surveillance: a management tool for occupational health

Epidemiological surveillance represents a practical and intuitive approach to preventing occupational disease and injury, yet it is underutilized in health care management. Through the systematic analysis of employee occupational health data, the epidemiological surveillance approach allows prompt identification of potential workplace hazards, identifies high-risk groups for targeting preventive efforts and provides a mechanism for evaluating interventions. Often, epidemiological surveillance can utilize existing data resources, making it a cost-effective tool. Epidemiological surveillance should be valuable in supporting management decisions relating to health promotion and disease prevention programs, as well as basic clinical needs of employees.     

The media/information richness model as prescription for some health care service ills

Because consumers are demanding more and better information from their health care providers, improving effectiveness and efficiency of communications is one way that health care providers can gain a competitive edge. The authors propose that health care communication effectiveness and efficiency can be improved by using the Media/Information Richness Model (MIR) in planning service delivery systems.     

An occupational cohort mortality study of women in the German rubber industry: 1976 to 1991.

Few previous studies of workers in the rubber industry have focused on women. We examined patterns of mortality among 2871 women employed in one of five German rubber plants for at least 1 year on or after January 1, 1976, and observed through December 31, 1991. All-causes mortality was near that expected (standardized mortality ratio [lsqbSMR], 101; 95% confidence interval [CI], 87 to 118), but cancer mortality was decreased (SMR, 90; 95% CI, 70 to 115). Nevertheless, excesses were observed for mortality from stomach cancer (SMR, 156; 95% CI, 63 to 322), lung cancer (SMR, 140; 95% CI, 56 to 289), and lymphatic system cancers (SMR, 175; 95% CI, 48 to 448). Stronger associations were observed among sub-cohorts defined by time period hired. Despite limited numbers of deaths, modest excesses of mortality due to specific cancers were observed and are consistent with previous studies.     

Differential typology among patients with hard and soft suicide methods

Two samples of patients admitted during one year after suicide attempts were compared: patients of the University Surgical Department in Heidelberg and a random sample of those who were admitted to the detoxication ward of the University Department for Internal Medicine. The frequency of patients who used "hard" methods was 10% of those using "soft" methods. Patients with hard suicide methods displayed more social desintegration, were more often psychiatrically ill, had a shorter presuicidal phase, a shorter time span from decision to execution of the suicidal attempt, more negative self-esteem and more chronic suicidality. Aggressiveness was low in both groups. Although the number of patients with "hard" suicidal methods is small and does not justify a special service in the Surgical Hospital, these patients need particularly careful supervision because of their psychopathological and psychosocial profile.     

Medical education about the care of addicted incarcerated persons: A national survey of residency programs

In June 1998, there were 1.8 million inmates in correctional facilities for adults; 1.2 million in state and federal prisons and 600,000 in municipal/county jails (668 persons per 100,000 U.S. population). Rates of TB, AIDS, mental illness, and substance abuse are 2–13 times higher in persons living in jails and prisons. This study was designed to assess the level of training offered to residents in seven medical specialties in the care of addicted incarcerated persons. The study design involved two stages. The first entailed a mailed survey to 1,831 residency directors in family medicine, internal medicine, osteopathic medicine, pediatrics, obstetrics and gynecology, psychiatry, and emergency medicine. The second stage was a telephone interview, about substance use disorders, of faculty listed by the residency directors as teaching residents. The mailed survey was completed by 1,205 residency directors (66%). The 769 faculty from those identified programs, who participated in the telephone interview, reported that only 14% of their residency programs offered lectures or conferences on the care of incarcerated persons, yet 44% of the programs had residents caring for incarcerated persons with substance abuse problems, in a clinical setting. Only 22% offered clinical experiences for residents in a correctional facility.

We recognize that our survey of correctional health and substance abuse training is limited, but as such, a greater number of respondents to our survey do not teach residents addiction medicine topics pertaining to prevention, evaluation, intervention, and management of the addicted criminal offender/patient in a correctional setting or give adequate clinical exposure to this special population. The data suggests a need to develop and implement educational programs on medical care for this high‐risk and expanding population.