Molluscan memory of injury: evolutionary insights into chronic pain and neurological disorders.

Molluscan preparations have yielded seminal discoveries in neuroscience, but the experimental advantages of this group have not, until now, been complemented by adequate molecular or genomic information for comparisons to genetically defined model organisms in other phyla. The recent sequencing of the transcriptome and genome of Aplysia californica, however, will enable extensive comparative studies at the molecular level. Among other benefits, this will bring the power of individually identifiable and manipulable neurons to bear upon questions of cellular function for evolutionarily conserved genes associated with clinically important neural dysfunction. Because of the slower rate of gene evolution in this molluscan lineage, more homologs of genes associated with human disease are present in Aplysia than in leading model organisms from Arthropoda (Drosophila) or Nematoda (Caenorhabditis elegans). Research has hardly begun in molluscs on the cellular functions of gene products that in humans are associated with neurological diseases. On the other hand, much is known about molecular and cellular mechanisms of long-term neuronal plasticity. Persistent nociceptive sensitization of nociceptors in Aplysia displays many functional similarities to alterations in mammalian nociceptors associated with the clinical problem of chronic pain. Moreover, in Aplysia and mammals the same cell signaling pathways trigger persistent enhancement of excitability and synaptic transmission following noxious stimulation, and these highly conserved pathways are also used to induce memory traces in neural circuits of diverse species. This functional and molecular overlap in distantly related lineages and neuronal types supports the proposal that fundamental plasticity mechanisms important for memory, chronic pain, and other lasting alterations evolved from adaptive responses to peripheral injury in the earliest neurons. Molluscan preparations should become increasingly useful for comparative studies across phyla that can provide insight into cellular functions of clinically important genes.

Current United States stem cell policy considerations and a recommendation for an alternative policy based on guidelines from existing international policies

Embryonic stem cell research is a widely debated topic in modern politics and religion. Differing views on the fetal rights conflict with the rights of an embryo. Those who believe an embryo has the same human qualities as a fetus accordingly believe embryonic stem cell research is unethical because it destroys a potential human life. However, scientists advocate the embryo does not have human qualities and should be used for valuable research in the stem cell field. Stem cell research may lead to vast developments in medical treatments, including cancer and brain conditions and injuries that are currently incurable. ^ The current stem cell policy introduced by President Bush in 2001 in an attempt to balance the moral issues with the need for scientific research has broad negative implications on the furthering of stem cell research. There is a limited diversity of available stem cell lines, there may be constitutional issues, there is an increasing disparity between the public and private research spheres, and the U.S. is struggling to maintain its scientific community. The U.S. must develop a new stem cell research policy that will balance the interest of science and public health with the moral issues that concern the public. ^ The United Kingdom allows researchers great liberty in conducting research, permitting the creation of embryos for the sole purpose of research, while Germany is equally conservative in their laws, as their policies support the philosophy that all embryos deserve the protection of full life. The United States should adopt a policy that takes the "middle ground" approach and permit research on excess embryos created for IVF purposes, rather than simply discarding those potentially valuable research tools. ^

BIOCHEMICAL CHARACTERIZATION AND CLINICAL SIGNIFICANCE OF COAGULASE-NEGATIVE STAPHYLOCOCCI

Although coagulase-negative staphylococci (C-NS) have been implicated in certain human infections, they are generally regarded as contaminants and their clinical significance is questioned. To assess their role as pathogens, 205 isolates of C-NS from wounds, and body fluids (blood, urine, pleural and peritoneal fluids, etc.) were studied. Patient's charts were reviewed and using strict criteria a determination was made regarding the clinical significance of these isolates. The organisms were then identified using the scheme of Kloos and Schleifer to determine if certain species of C-NS were associated with specific infections. S. epidermidis sensu stricto accounted for 81% of the C-NS isolated; the frequency of other species was S. haemolyticus (6%), S. hominis (5%), S. capitis (4%), S. warneri (3%), and others (1%). Only two isolates were novobiocin resistant; neither was identified as S. saprophyticus. Using these criteria, 22% of C-NS were considered to be clinically significant and the majority of these (93%) were due to S. epidermidis. The most common source of the clinically relevant C-NS isolates was from wounds. These data suggest that identifying C-NS species other than S. epidermidis may be of limited value in predicting clinical significance.^ In addition, selected pathogenic and non-pathogenic strains of C-NS were compared for their ability to adhere to human cells in vitro. Although the results were not conclusive, it appeared that pathogenic C-NS adhered more avidly than non-pathogenic C-NS to buccal cells. Experiments with HeLa cells showed no difference between pathogenic and non-pathogenic C-NS in adherence abilities. ^

Occupational injuries among day laborers in Houston

Research has indicated that day laborers engage in higher risk occupations and suffer a high number of occupationally related fatal and non-fatal injuries. Although there have been some studies focusing on immigrant workers and their occupational injuries, none to our knowledge has studied Houston’s day laborers. An exploratory study of Houston’s day laborer population was conducted in 2008 by Dr. Fernández-Esquer from the University of Texas. ^ The aims of the current study are to analyze secondary data from this parent study and describe the prevalence of the self reported occupational injuries among Houston immigrant day laborers seeking work during the months of October through December 2008. The study also aims to determine if the reported injuries varied by age group, education level, length of time living in the U.S. and length of time working as day laborers and describe if injuries were more common by the number of different job types or job conditions reported or the use of personal protective equipment used (PPE). ^ This study analyzed 325 questionnaires that included job-related information from the parent study. One hundred and nine workers (35 %) reported an occupational injury or illness in the year before the interview. The most frequent injuries or illnesses reported were falls (26.7 %), cuts and lacerations (23.3 %) and being struck by an object (18.3 %). Over half of the workers (57 %) reported working 4 to 6 different jobs in the year before the interview, followed by 22.5 % reporting 1 to 3 different jobs. A combined 79 % of day laborers in Houston reported exposure to 7 or more of the job conditions listed and 69 % of those workers also reported an injury or illness. PPE use varied from 44 % of workers reporting using 4 to 6 PPE items to 6.8 % reporting not using any type of PPE. Thirty two percent of workers reporting not using any PPE also reported an injury or illness. ^ Injuries were found not to have varied significantly by age group, time living in the US, time working as a day laborer, numbers of different job types and the number of PPE used. Injuries did vary significantly by education level of the participants and the number of different job conditions reported (education, X2 (4, N = 315) = 12.651, p =0.013; and job conditions, X2 (3, N = 319) = 14.698, p = 0.002). ^ Although this first study of Houston’s day laborers was successful at engaging the population and getting background information regarding the occupational health of these workers, more studies are needed to further characterize the day laborers occupational experiences and injuries along with determining what specific job types and job conditions were present when injuries occurred and what kind of PPE was being used at the time. It is also clear that these workers need better safety training programs regarding working in potentially dangerous jobs and job conditions. They would also benefit from programs that would help empower them to negotiate for safer conditions.^

Changing epidemiology of trauma deaths leads to a bimodal distribution

Introduction. Injury mortality was classically described with a tri-modal distribution, with immediate deaths at the scene, early deaths due to hemorrhage, and late deaths from organ failure. We hypothesized that trauma systems development have improved pre-hospital care, early resuscitation, and critical care, and altered this pattern. ^ Methods. This is a population-based study of all trauma deaths in an urban county with a mature trauma system (n=678, median age 33 years, 81% male, 43% gunshot, 20% motor vehicle crashes). Deaths were classified as immediate (scene), early (in hospital, ≤ 4 hours from injury), or late (>4 hours post injury). Multinomial regression was used to identify independent predictors of immediate and early vs. late deaths, adjusted for age, gender, race, intention, mechanism, toxicology and cause of death. ^ Results. There were 416 (61%) immediate, 199 (29%) early, and 63 (10%) late deaths. Immediate deaths remained unchanged and early deaths occurred much earlier (median 52 minutes vs. 120). However, unlike the classic trimodal distribution, there was no late peak. Intentional injuries, alcohol intoxication, asphyxia, and injuries to the head and chest were independent predictors of immediate deaths. Alcohol intoxication and injuries to the chest were predictors of early deaths, while pelvic fractures and blunt assaults were associated with late deaths. ^ Conclusion. Trauma deaths now have a bimodal distribution. Elimination of the late peak likely represents advancements in resuscitation and critical care that have reduced organ failure. Further reductions in mortality will likely come from prevention of intentional injuries, and injuries associated with alcohol intoxication. ^

Implementing the Global Plan of Action on workers' health: Components to protect health care workers

Health care workers are at risk for percutaneous injuries and infection with blood born pathogens due to needle stick injuries with contaminated needles. The most common pathogens transmitted are hepatitis B, and C and HIV/AIDS. According to the WHO Global Plan of Action (GPA) a large gap exist between and within countries with regards to the health status of workers and their exposure to occupational risk. Less than 15% of the world's work forces have access to occupational health services despite the availability of effective interventions that can prevent occupational hazards, or protect and promote health in the workplace. The 2006 World Health Report declared that there is a global crisis in the health care work force. 1 in 400 of the world's health care workers work in Sub-Saharan Africa. 1 in 3 work in the U.S or Canada. The shortage of health care workers is worst in Southeast Asia and Sub-Saharan Africa. These countries have the highest burden of exposure to contaminated sharps. They rarely, if ever monitor the exposure or health impact of occupational ailments and injuries on workers. Many injuries are unreported. Occupational health services in the developing world are virtually non existent. Many health care workers leave their home countries and go to work in other countries where the working conditions, occupational services included, are better. The inability of countries to provide the necessary numbers of health care workers to provide a high level of health coverage is a threat to national and international public health security. Immunizing health care workers against hepatitis B and providing them PEP, PPE, education and safety training is an essential part of increasing and maintaining the numbers of health care workers in the critical shortage areas. ^

A case-control study to identify risk factors for preterm labor in Colorado Springs, Colorado

The study objectives were to determine risk factors for preterm labor (PTL) in Colorado Springs, CO, with emphasis on altitude and psychosocial factors, and to develop a model that identifies women at high risk for PTL. Three hundred and thirty patients with PTL were matched to 460 control patients without PTL using insurance category as an indirect measure of social class. Data were gathered by patient interview and review of medical records. Seven risk groups were compared: (1) Altitude change and travel; (2) Psychosocial ((a) child, sexual, spouse, alcohol and drug abuse; (b) neuroses and psychoses; (c) serious accidents and injuries; (d) broken home (maternal parental separation); (e) assault (physical and sexual); and (f) stress (emotional, domestic, occupational, financial and general)); (3) demographic; (4) maternal physical condition; (5) Prenatal care; (6) Behavioral risks; and (7) Medical factors. Analysis was by logistic regression. Results demonstrated altitude change before or after conception and travel during pregnancy to be non-significant, even after adjustment for potential confounding variables. Five significant psychosocial risk factors were determined: Maternal sex abuse (p = 0.006), physical assault (p = 0.025), nervous breakdown (p = 0.011), past occupational injury (p = 0.016), and occupational stress (p = 0.028). Considering all seven risk groups in the logistic regression, we chose a logistic model with 11 risk factors. Two risk factors were psychosocial (maternal spouse abuse and past occupational injury), 1 was pertinent to maternal physical condition ($\le$130 lbs. pre-pregnancy weight), 1 to prenatal care ($\le$10 prenatal care visits), 2 pertinent to behavioral risks ($>$15 cigarettes per day and $\le$30 lbs. weight gain) and 5 medical factors (abnormal genital culture, previous PTB, primiparity, vaginal bleeding and vaginal discharge). We conclude that altitude change is not a risk factor for PTL and that selected psychosocial factors are significant risk factors for PTL. ^

Outcomes of truncal vascular injuries in children.

BACKGROUND: Pediatric truncal vascular injuries occur infrequently and have a reported mortality rate of 30% to 50%. This report examines the demographics, mechanisms of injury, associated trauma, and outcome of patients presenting for the past 10 years at a single institution with truncal vascular injuries. METHODS: A retrospective review (1997-2006) of a pediatric trauma registry at a single institution was undertaken. RESULTS: Seventy-five truncal vascular injuries occurred in 57 patients (age, 12 +/- 3 years); the injury mechanisms were penetrating in 37%. Concomitant injuries occurred with 76%, 62%, and 43% of abdominal, thoracic, and neck vascular injuries, respectively. Nonvascular complications occurred more frequently in patients with abdominal vascular injuries who were hemodynamically unstable on presentation. All patients with thoracic vascular injuries presenting with hemodynamic instability died. In patients with neck vascular injuries, 1 of 2 patients who were hemodynamically unstable died, compared to 1 of 12 patients who died in those who presented hemodynamically stable. Overall survival was 75%. CONCLUSIONS: Survival and complications of pediatric truncal vascular injury are related to hemodynamic status at the time of presentation. Associated injuries are higher with trauma involving the abdomen.

A descriptive and exploratory analysis of occupational injuries at a chemical manufacturing facility

A retrospective study of 1353 occupational injuries occurring at a chemical manufacturing facility in Houston, Texas from January, 1982 through May, 1988 was performed to investigate the etiology of the occupational injury process. Injury incidence rates were calculated for various sub-populations of workers to determine differences in the risk of injury for various groups. Linear modeling techniques were used to determine the association between certain collected independent variables and severity of an injury event. Finally, two sub-groups of the worker population, shiftworkers and injury recidivists, were examined. An injury recidivist as defined is any worker experiencing one or more injury per year. Overall, female shiftworkers evidenced the highest average injury incidence rate compared to all other worker groups analyzed. Although the female shiftworkers were younger and less experienced, the etiology of their increased risk of injury remains unclear, although the rigors of performing shiftwork itself or ergonomic factors are suspect. In general, females were injured more frequently than males, but they did not incur more severe injuries. For all workers, many injuries were caused by erroneous or foregone training, and risk taking behaviors. Injuries of these types are avoidable. The distribution of injuries by severity level was bimodal; either injuries were of minor or major severity with only a small number of cases falling in between. Of the variables collected, only the type of injury incurred and the worker's titlecode were statistically significantly associated with injury severity. Shiftworkers did not sustain more severe injuries than other worker groups. Injury to shiftworkers varied as a 24-hour pattern; the greatest number occurred between 1200-1230 hours, (p = 0.002) by Cosinor analysis. Recidivists made up 3.3% of the population (23 males and 10 females), yet suffered 17.8% of the injuries. Although past research suggests that injury recidivism is a random statistical event, analysis of the data by logistic regression implicates gender, area worked, age and job titlecode as being statistically significantly related to injury recidivism at this facility. ^

Penetrating injuries of the thorax and abdomen: Type of medical-care institution and case fatality

The purpose of this study was to determine, for penetrating injuries (gunshot, stab) of the chest/abdomen, the impact on fatality of treatment in trauma centers and shock trauma units compared with general hospitals. Medical records of all cases of penetrating injury limited to chest/abdomen and admitted to and discharged from 7 study facilities in Baltimore city 1979-1980 (n = 581) were studied: 4 general hospitals (n = 241), 2 area-wide trauma centers (n = 298), and a shock trauma unit (n = 42). Emergency center and transferred cases were not studied. Anatomical injury severity, measured by modified Injury Severity Score (mISS), was a significant prognostic factor for death, as were cardiovascular shock (SBP $\le$ 70), injury type (gunshot vs stab), and ambulance/helicopter (vs other) transport. All deaths occurred in cases with two or more prognostic factors. Unadjusted relative risks of death compared with general hospitals were 4.3 (95% confidence interval = 2.2, 8.4) for shock trauma and 0.8 (0.4, 1.7) for trauma centers. Controlling for prognostic factors by logistic regression resulted in these relative risks: shock trauma 4.0 (0.7, 22.2), and trauma centers 0.8 (0.2, 3.2). Factors significantly associated with increased risk had the following relative risks by multiple logistic regression: SBP $\le$ 70 (RR = 40.7 (11.0, 148.7)), highest mISS (42 (7.7, 227)), gunshot (8.4 (2.1, 32.6)), and ambulance/helicopter transport (17.2 (1.3, 228.1)). Controlling for age, race, and gender did not alter results significantly. Actual deaths compared with deaths predicted from a multivariable model of general-hospital cases showed 3.7 more than predicted deaths in shock trauma (SMR = 1.6 (0.8, 2.9)) and 0.7 more than predicted deaths in area-wide trauma centers (SMR = 1.05 (0.6, 1.7)). Selection bias due to exclusion of transfers and emergency center cases, and residual confounding due to insufficient injury information, may account for persistence of adjusted high case fatality in shock trauma. Studying all cases prospectively, including emergency center and transferred cases, is needed. ^

AN EPIDEMIOLOGIC DESCRIPTION AND ANALYSIS OF LOST WORKDAY OCCUPATIONAL BURN INJURIES

Background research consisted of a hospital case series of all adult burn patients (n = 162) admitted to John Sealy Hospital's burn unit from January 1978 to June 1979. Comparisons between occupationally and nonoccupationally burned adults demonstrated that occupationally burned adults were significantly more likely to have been active in the burn injury event and to have changed jobs during the prior year. They were significantly less likely to have physical or mental problems which contributed to sustaining the burn injury. Comparisons between occupational and nonoccupational burn injury events concluded that occupational burn injury events were significantly more likely to involve multiple sources of energy, sparks as the source of ignition and gases as the source of combustion. Other salient characteristics of occupational burn injuries indicated that subsequent research should focus upon lost workday occupational burns and other injuries sustained by blue-collar petrochemical workers employed in Galveston County, Texas.^ Subsequent research consisted of a historical cohort study of occupational injuries sustained in 1979 by a cohort of blue-collar petrochemical workers (n = 1771) who belonged to O.C.A.W. Local 4-449 in Texas City, Texas. Specific cohort injury rates included 15.08 occupational injuries per 100 person work-years, 11.98 lost workday occupational injuries per 100 person work-years, and 1.64 lost workday occupational burn injuries per 100 person work-years. Salient results from this study indicate that burn injuries are a very important type (in terms of both frequency and severity) of occupational injury sustained by blue-collar petrochemical workers, pipefitters are at greatest risk of lost workday injuries and lost workday burn injuries, company-specific experiences are comparable for lost workday occupational injuries, differences among company-specific nonlost workday occupational injury experiences may not be "safety-related", and minimal job-specific experience may not place employees at greater risk of lost workday burn injuries.^