Biostimulation with oxygen and electron donors supports micropollutant biodegradation in an experimentally simulated nitrate-reducing aquifer

The availability of suitable electron donors and acceptors limits micropollutant natural attenuation in oligotrophic groundwater. This study investigated how electron donors with different biodegradability (humics, dextran, acetate, and ammonium), and different oxygen concentrations affect the biodegradation of 15 micropollutants (initial concentration of each micropollutant = 50 μg/L) in simulated nitrate reducing aquifers. Tests mimicking nitrate reducing field conditions showed no micropollutant biodegradation, even with electron donor amendment. However, 2,4-dichlorophenoxyacetic acid and mecoprop were biodegraded under (micro)aerobic conditions with and without electron donor addition. The highest 2,4-dichlorophenoxyacetic acid and mecoprop biodegradation rates and removal efficiencies were obtained under fully aerobic conditions with amendment of an easily biodegradable electron donor. Under microaerobic conditions, however, amendment with easily biodegradable dissolved organic carbon (DOC) inhibited micropollutant biodegradation due to competition between micropollutants and DOC for the limited oxygen available. Microbial community composition was dictated by electron acceptor availability and electron donor amendment, not by micropollutant biodegradation. Low microbial community richness and diversity led to the absence of biodegradation of the other 13 micropollutants (such as bentazon, chloridazon, and carbamazepine). Finally, adaptation and potential growth of biofilms interactively determined the location of the micropollutant removal zone relative to the point of amendment. This study provides new insight on how to stimulate in situ micropollutant biodegradation to remediate oligotrophic groundwaters as well as possible limitations of this process.

Intestinal macrophages in pathogenesis and treatment of gut leakage: current strategies and future perspectives

Macrophages play key roles in tissue homeostasis, defense, disease, and repair. Macrophages are highly plastic and exhibit distinct functional phenotypes based on micro-environmental stimuli. In spite of several advancements in understanding macrophage biology and their different functional phenotypes in various physiological and pathological conditions, currently available treatment strategies targeting macrophages are limited. Macrophages' high plasticity and diverse functional roles-including tissue injury and wound healing mechanisms-mark them as potential targets to mine for efficient therapeutics to treat diseases. Despite mounting evidence on association of gut leakage with several extraintestinal diseases, there is no targeted standard therapy to treat gut leakage. Therefore, there is an urgent need to develop therapeutic strategies to treat this condition. Macrophages are the cells that play the largest role in interacting with the gut microbiota in the intestinal compartment and exert their intended functions in injury and repair mechanisms. In this review, we have summarized the current knowledge on the origins and phenotypes of macrophages. The specific role of macrophages in intestinal barrier function, their role in tissue repair mechanisms, and their association with gut microbiota are discussed. In addition, currently available therapies and the putative tissue repair mediators of macrophages for treating microbiota dysbiosis induced gut leakage are also discussed. The overall aim of this review is to convey the intense need to screen for microbiota induced macrophage-released prorepair mediators, which could lead to the identification of potential candidates that could be developed for treating the leaky gut and associated diseases.

Interaction between mitochondria and microbiota modulating cellular metabolism in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a prototypic complex disease in the gastrointestinal tract that has been increasing in incidence and prevalence in recent decades. Although the precise pathophysiology of IBD remains to be elucidated, a large body of evidence suggests the critical roles of mitochondria and intestinal microbiota in the pathogenesis of IBD. In addition to their contributions to the disease, both mitochondria and gut microbes may interact with each other and modulate disease-causing cell activities. Therefore, we hypothesize that dissecting this unique interaction may help to identify novel pathways involved in IBD, which will further contribute to discovering new therapeutic approaches to the disease. As poorly treated IBD significantly affects the quality of life of patients and is associated with risks and complications, successful treatment is crucial. In this review, we stratify previously reported experimental and clinical observations of the role of mitochondria and intestinal microbiota in IBD. Additionally, we review the intercommunication between mitochondria, and the intestinal microbiome in patients with IBD is reviewed along with the potential mediators for these interactions. We specifically focus on their roles in cellular metabolism in intestinal epithelial cells and immune cells. To this end, we propose a potential therapeutic intervention strategy for IBD.

Antibacterial and Antibiofilm Efficacy of Copper-Doped Phosphate Glass on Pathogenic Bacteria

This study aimed to investigate the antibacterial [minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)] and antibiofilm activity [log10 colony forming unit/mL (CFU/mL) and biofilm disruption] of copper-doped phosphate glass (CDPG) against Streptococcus oralis, Enterococcus faecalis, Lactobacillus casei, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Methods: the antibacterial activity was determined using microbroth dilution and time-kill assay. The antibiofilm activity was investigated using crystal violet and confocal laser scanning microscopy. Bacteria growing in absence of CDPG were used as controls. Results: the MIC was ≥125 mg of CPDG/mL; the log10 CFU/mL reduction ranged from 2.66–3.14 to 6.23–9.65 after 4 and 24 h respectively. Generally, no growth was observed after 24 h of treatment with CDPG; the MBC was 250 mg/mL for L. casei and S. oralis while 500 mg/mL for the rest of the bacteria. The highest and lowest antibiofilm activity was observed against S. oralis and E. coli respectively. Three patterns of complete biofilm disruption were seen: (i) large areas with E. fecalis and S. oralis, (ii) medium-size pockets with S. aureus and P. aeruginosa, or (iii) small areas with E. coli and L. casei. Conclusion: CDPG can be potentially used as an antibacterial and an antibiofilm agent against oral biofilm-forming bacteria.

Formulation of In-situ Thermoreversible Gel with Moringa oleifera Lam Extract as a Local Drug Delivery System for Adjunct Periodontal Treatment

Introduction: Periodontal disease is an outcome of a plethora of molecular mechanisms associated with oxidative stress, inflammation and oral microorganisms is managed by surgical or non surgical therapies with systemic antibiotics. However, local drug delivery system is known to augment the currently available therapies and improves prognosis. Although, there are several local drug delivery systems available, the search for an ideal agent with antioxidant, antimicrobial and anti-inflammatory properties continues. Moringa oleifera Lam extracts is one such wonder plant with all the above mentioned effects. Aim: To formulate an in-situ thermoreversible gel with Moringa oleifera Lam extract that could be used as a local drug delivery system as an adjunct to periodontal treatment. Materials and Methods: This in-vitro study was conducted in Nanotechnology Laboratory, Department of Pharmacology at Saveetha Dental College, from May 2022 to June 2022. For preparation of thermoreversible gel the 19% of thermogelling polymer poloxamer 407 (15% to 30%w/v) which the least concentration that demonstrates thermoreverisibility at 36°C and 0.2% which is the least concentration of mucoadhesive polymer carbapol 934 (0.2% to 0.5% w/v) which forms sol-gel transition and 5% aqueous extract of Moringa oleifera and cold deionised water were used. Surface pH, gelation temperature, syringeability, in-vitro drug release, stability, gelation time and Fourier Transform Infrared Spectroscopy (FTIR) analysis was done Results: The surface pH of the gel was 6.94±0.091 with a gelation temperature of 34°C±0.5. The gel was flowable with good stability and fast release of eight hours. The chemical components compatability study of Moringa oleifera Lam powder, thermoreversible gel without extract and thermoreversible gel with extract were subjected to FITR analysis. The spectral analysis showed no significant chemical interaction between the Moringa oleifera and thermoreversible gel. Conclusion: The study concluded that the thermoreversible gel with Moringa oleifera Lam extracts could be used as an adjunct for the management of periodontal disease with good bioavailability. However, future clinical studies have to be conducted to validate the results of the present study.

Considerations in Real-time Reverse Transcription Polymerase Chain Reaction (rRT-PCR) for the Detection of SARS-CoV-2 from Nasopharyngeal Swabs

Coronavirus Disease 2019 (COVID-19) was first reported in December 2019, in the City of Wuhan, China. Within the span of a few weeks, the disease had spread to other regions of China and eventually to different parts of the world. COVID 19 has affected 221 countries and territories around the world, with a total of 121,290,697 positive cases and 2,682,554 deaths as on March 17, 2021. Accurate disease diagnosis (for the SARS-Cov-2 virus and variants), coupled to patient isolation are currently critical strategies in restricting disease spread. Due to lack of time during this pandemic the diagnostics assays were not adequately validated. Infected individuals at times could potentially be missed by real-time reverse transcription polymerase chain reaction (rRT-PCR) for SARS-CoV-2 tests due to incorrect/inefficient sampling procedure, low limit of detection and epidemiology of the virus. rRT-PCR test results should be interpreted in conjunction with clinical examination and Computed Tomography (CT), particularly in suspected symptomatic individuals or those with epidemiological history of contact with known COVID-19 cases. Considering the above-mentioned constraints, the current scenario demands rapid and point-of-care tests for detection of SARS-CoV-2 in remote locations. To date, there is no reliable commercially available antigen detection kit. The infected subjects reveal low levels of antibodies against SARS-CoV-2 through the early period of infection. In addition, techniques such as, Digital RT-PCR technology and isothermal RNA amplification with electrochemical biosensors are some of the new technologies currently being developed to provide sensitive and specific SARS-Cov-2 antigen detection. The newly reported variant, SARS-CoV-2 VUI 202012/01 may not influence diagnostic outcomes as worldwide most PCR assays use two or more (including RdRp/ E/ N) reliable gene targets, besides S gene.

Burden of caregivers of children with cerebral palsy: an intersectional analysis of gender, poverty, stigma, and public policy

Background

Caregivers of children with cerebral palsy suffer from a substantial psychosocial burden. However, there is a scarcity of documentation of the various sources of burden in low- and middle-income settings.

Methods

We conducted qualitative in-depth interviews among mothers of children with cerebral palsy attending a physiotherapy facility. We purposively sampled mothers from rural and peri-urban areas in Tamil Nadu, India, till the point of data saturation. We analysed the transcripts using the socio-ecological model to identify the major dimensions of psychosocial burden among these mothers.

Results

At the individual level the mothers perceived aches and pains due to the heavy physical activity of caregiving. They also suffered from a feeling of guilt about the child’s condition. Due to the difficulty in balancing family and work, they had significant financial burdens. They also perceived a lack of knowledge and awareness about possible options for the treatment of their child. At the interpersonal level, the mothers lacked support from their husband and family in the process of caregiving. They also had to suffer the ill effects of alcoholism and domestic violence from their husbands. They had to compromise on the care they provided to the other family members and their children without cerebral palsy. At the community level, the mothers had no support from the community members and felt isolated from others. The mothers also reported discrimination and lack of participation in social events. Environmental stressors like lack of inclusive public spaces, lack of options for public transport and unfriendly work timings and environment were major sources of burden. The mothers felt that the disability welfare support offered by the government was grossly insufficient and there was no platform for interactions with other peers and mothers suffering from a similar burden.

Conclusion

Caregivers of children with cerebral palsy have unique burdens in a typical low- and middle-income setting including an intersection of gender norms, poverty, stigmatization and non-inclusive public policy, which need to be addressed to improve the quality of life of caregivers.

Whole genome sequence analysis of NDM-1, CMY-4, and SHV-12 coproducing Salmonella enterica serovar Typhimurium isolated from a case of fatal burn wound infection

Salmonella species are frequently associated with gastrointestinal infections such as diarrhea. However, extraintestinal Salmonella infections, including burn infections, have been described. Here, we report the first case of a carbapenem-resistant and metallo-β-lactamase (New Delhi metallo-β-lactamase), extended-spectrum β-lactamase (SHV-12), and AmpC β-lactamase (CMY-4) coproducing Salmonella Typhimurium isolated from a fatal case of burn wound infection. The publication highlights the necessity for the rational use of antibiotics (particularly the rational use of last-resort antibiotics such as carbapenems) in hospitals and burn units, as well as the need for systematic screening of Salmonella spp. (including Salmonella enterica serovar Typhimurium) for resistance to carbapenem antibiotics.

Epidemiology of diabetic foot infections in a reference tertiary hospital in India

Introduction

The present study attempts to examine the microbial profile and antibiotic susceptibility of diabetic foot infections in the intensive care unit of a tertiary referral centre for diabetic foot. As part of the study, we also attempted to find the prevalence of blaNDM-like gene among carbapenem-resistant gram negative infections.

Methodology

A prospective study of 261 patients with diabetic foot infections was performed during the period between January 2014 and June 2014.

Results

A total of 289 isolates were obtained from 178 tissue samples from 261 patients, 156 (59.7%) males and 105 (40.2%) females, with a mean age of 58 years (−15 years), having diabetic foot infection. No growth was seen in thirty eight (17.6%) tissue samples. Out of the total samples, 44.3% were monomicrobial and 55.7% were polymicrobial. Gram negative pathogens were predominant (58.5%). Seven of the total isolates were fungal; 0.7% showed pure fungal growth and 1.7% were mixed, grown along with some bacteria. The most frequently isolated bacteria were Staphylococcus aureus (26.9%), followed by Pseudomonas aeruginosa (20.9%). Of the 58.5% gram negative pathogens, 16.5% were Enterobacteriaceae resistant to carbapenems. Among these isolates, 4 (25%) were positive for blaNDM-like gene. Among the rest, 18.6% were carbapenem-resistant Pseudomonas, among which 4 (36.3%) were blaNDM. Among the Staphylococci, 23.7% were methicillin-resistant Staphylococcus aureus.

Conclusions

Our results support the recent view that gram negative organisms, depending on the geographical location, may be predominant in DFIs. There is an increase in multidrug-resistant pathogens, especially carbapenem resistance and this is creeping rapidly. We need to be more judicious while using empiric antibiotics.

Self-preserving personal care products

OBJECTIVE

As questions on the safety of some popular preservatives are on the rise, there is a growing interest in developing 'self-preserving' personal care products. Use of multifunctional ingredients/actives with antimicrobial properties has been explored as replacements for conventional preservatives. This study explores the use of combinations of multifunctional actives (MFA) and other cosmetic ingredients in various personal care formulations, to deliver microbiologically safe self-preserving products. Products studied in this study include face wash, gel-based leave-on skin care product and face mask.

METHODS

Minimum inhibitory concentration (MIC) of several cosmetic ingredients was determined to identify multifunctional actives with antimicrobial activity. Personal care formulations made with multifunctional actives and other cosmetic ingredients were studied for preservative efficacy by challenging the product with six multiple cycles of microbial challenge.

RESULTS

Formulations with combinations of multifunctional actives with antioxidant (AO) and chelators (CHL) were found to work synergistically and were highly efficacious in controlling multiple microbial challenges as observed in the preservative efficacy test (PET) studies. The effective combinations were able to withstand up to six multiple microbial challenges without product degradation. The preservative efficacy profile was similar to control formula containing preservatives.

CONCLUSION

Self-preserving personal care/cosmetic products can be developed which are as efficacious as preserved products by a prudent selection of multifunctional actives, antioxidants and chelators as a part of the formulation.

Changes in fetal cardiac axis between 8 and 15 weeks' gestation

OBJECTIVES

To document changes in the normal embryonic/fetal cardiac axis in the late first and early second trimesters of pregnancy.

METHODS

Images from 188 fetal echocardiograms performed prospectively between 8 and 15 weeks' gestation in 166 healthy pregnancies and in 10 pregnancies with severe fetal heart disease were reviewed. For each echocardiogram, three measurements of the cardiac axis were taken in the axial plane at the level of the four-chamber view. Differences in mean embryonic/fetal cardiac axis at different gestational ages in the healthy pregnancies were compared.

RESULTS

The mean ± SD embryonic/fetal cardiac axis was 25.5 ± 11.5° from 8 + 0 to 9 + 6 weeks (Group  1), 40.4 ± 9.2° from 10 + 0 to 11 + 6 weeks (Group  2), 49.2 ± 7.4° from 12 + 0 to 12 + 6 weeks (Group  3), 50.6 ± 5.7° from 13 + 0 to 13 + 6 weeks (Group 4) and 48.6 ± 7.3° from 14 + 0 to 14 + 6 weeks (Group 5). Groups 1 and 2 were significantly different from each other and all other groups (P < 0.05). The results for 22 cases with repeat measurements from 8 + 0 to 11 + 6 and 12 + 0 to 14 + 6 weeks confirmed that the embryonic/fetal cardiac axis increased significantly (P < 0.001). In the cases with severe congenital heart disease, the cardiac axis was > 90th centile in four cases and < 10th centile in two cases.

CONCLUSIONS

The embryonic cardiac axis is relatively midline at 8 weeks and levorotates in the late first trimester. By 12 weeks' gestation, the normal leftward fetal cardiac axis is established and remains stable until at least 14 + 6 weeks. Observation of an abnormal cardiac axis in some cases of severe congenital heart disease prior to 15 weeks' gestation may assist in prenatal detection.

Health-care utilization and respiratory morbidities in preterm infants with pulmonary hypertension

OBJECTIVE

To assess health-care utilization and risk of respiratory morbidities in preterm infants with bronchopulmonary dysplasia (BPD) and pulmonary hypertension (PH).

STUDY DESIGN

Retrospective data were obtained from subjects (n=109) attending a BPD clinic. Subjects were stratified by the presence or absence of PH before and after 2 months of age. Analytic methods included t-tests, χ(2) tests and regression.

RESULT

Subjects with BPD and PH present after 2 months of age were hospitalized for 2.2 months longer than those without PH (P=0.02). These subjects were 4.5 times more likely to receive home supplemental oxygen or mechanical ventilation (P=0.03). No difference in the risk of respiratory morbidities after initial hospital discharge was seen with PH.

CONCLUSION

PH in preterm infants is associated with longer initial hospitalizations and a higher likelihood of requiring home respiratory support. This has implications for counseling families and reducing the medical, psychosocial, and economic burden of BPD and PH.

A case of restrictive cardiomyopathy presenting in fetal life with an isolated pericardial effusion

We describe the evolution during pregnancy of a case of restrictive cardiomyopathy which first presented at 22 weeks' gestation with a large pericardial effusion. Measurements of cardiac function were normal and remained near normal until late in the third trimester, when pulsed and tissue Doppler data suggested impairment in ventricular relaxation. This disease progressed in postnatal life to symptomatic restrictive cardiomyopathy by 2 years of age necessitating cardiac transplant. To our knowledge, this is the first time this unusual association has been reported.

Smoking and family history and risk of aneurysmal subarachnoid hemorrhage

OBJECTIVE

Smoking and family history of aneurysmal subarachnoid hemorrhage (aSAH) are independent risk factors for aSAH. Using a population-based case-control study of hemorrhagic stroke, we hypothesized that having both a first-degree relative with a brain aneurysm or SAH (+FH) and current smoking interact to increase the risk of aSAH.

METHODS

Cases of aneurysmal SAH were prospectively recruited from all 17 hospitals in the five-county region around the University of Cincinnati. Controls were identified by random digit dialing. Controls were matched to cases of aSAH by age (+/-5 years), race, and sex. Conditional multiple logistic regression was used to identify independent risk factors. For deviation from the additive model, the interaction constant ratio test was used.

RESULTS

A total of 339 cases of aSAH were matched to 1,016 controls. Compared to current nonsmokers with no first-degree relatives with aSAH (-FH), the odds ratio (OR) for aSAH for current nonsmokers with +FH was 2.5 (95% confidence interval [CI] 0.9-6.9); for current smokers with -FH, OR = 3.1 (95% CI 2.2-4.4); and for current smokers with +FH, OR = 6.4 (95% CI 3.1-13. 2). The interaction constant ratio, which measured the deviation from the additive model, was significant: 2.19 (95% CI 0.80-5.99). The lower bound of the 95% CI >0.5 signifies a departure from the additive model.

CONCLUSION

Evidence of a gene-environment interaction with smoking exists for aneurysmal subarachnoid hemorrhage. This finding is important to counseling family members and for screening of intracranial aneurysm (IA) as well as the design and interpretation of genetic epidemiology of IA studies.

Warfarin use leads to larger intracerebral hematomas

BACKGROUND

Among patients with intracerebral hemorrhage (ICH), warfarin use before onset leads to greater mortality. In a retrospective study, we sought to determine whether warfarin use is associated with larger initial hematoma volume, one determinant of mortality after ICH.

METHODS

We identified all patients hospitalized with ICH in the Greater Cincinnati region from January through December 2005. ICH volumes were measured on the first available brain scan by using the abc/2 method. Univariable analyses and a multivariable generalized linear model were used to determine whether international normalized ratio (INR) influenced initial ICH volume after adjusting for other factors, including age, race, sex, antiplatelet use, hemorrhage location, and time from stroke onset to scan.

RESULTS

There were 258 patients with ICH, including 51 patients taking warfarin. In univariable comparison, when INR was stratified, there was a trend toward a difference in hematoma volume by INR category (INR <1.2, 13.4 mL; INR 1.2-2.0, 9.3 mL; INR 2.1-3.0, 14.0 mL; INR >3.0, 33.2 mL; p = 0.10). In the model, compared with patients with INR <1.2, there was no difference in hematoma size for patients with INR 1.2-2.0 (p = 0.25) or INR 2.1-3.0 (p = 0.36), but patients with INR >3.0 had greater hematoma volume (p = 0.02). Other predictors of larger hematoma size were ICH location (lobar compared with deep cerebral, p = 0.02) and shorter time from stroke onset to scan (p < 0.001).

CONCLUSION

Warfarin use was associated with larger initial intracerebral hemorrhage (ICH) volume, but this effect was only observed for INR values >3.0. Larger ICH volume among warfarin users likely accounts for part of the excess mortality in this group.

The increasing incidence of anticoagulant-associated intracerebral hemorrhage

OBJECTIVE

To define temporal trends in the incidence of anticoagulant-associated intracerebral hemorrhage (AAICH) during the 1990s and relate them to rates of cardioembolic ischemic stroke.

METHODS

We identified all patients hospitalized with first-ever intracerebral hemorrhage (ICH) in greater Cincinnati during 1988, from July 1993 through June 1994, and during 1999. AAICH was defined as ICH in patients receiving warfarin or heparin. Patients from the same region hospitalized with first-ever ischemic stroke of cardioembolic mechanism were identified during 1993/1994 and 1999. Incidence rates were calculated and adjusted to the 2000 US population. Estimates of warfarin distribution in the United States were obtained for the years 1988 through 2004.

RESULTS

AAICH occurred in 9 of 184 ICH cases (5%) in 1988, 23 of 267 cases (9%) in 1993/1994, and 54 of 311 cases (17%) in 1999 (p < 0.001). The annual incidence of AAICH per 100,000 persons was 0.8 (95% CI 0.3 to 1.3) in 1988, 1.9 (1.1 to 2.7) in 1993/1994, and 4.4 (3.2 to 5.5) in 1999 (p < 0.001 for trend). Among persons aged > or =80, the AAICH rate increased from 2.5 (0 to 7.4) in 1988 to 45.9 (25.6 to 66.2) in 1999 (p < 0.001 for trend). Incidence rates of cardioembolic ischemic stroke were similar in 1993/1994 and 1999 (31.1 vs 30.4, p = 0.65). Warfarin distribution in the United States quadrupled on a per-capita basis between 1988 and 1999.

CONCLUSIONS

The incidence of anticoagulant-associated intracerebral hemorrhage quintupled in our population during the 1990s. The majority of this change can be explained by increasing warfarin use. Anticoagulant-associated intracerebral hemorrhage now occurs at a frequency comparable to subarachnoid hemorrhage.

Long-term mortality after intracerebral hemorrhage

OBJECTIVE

To characterize long-term mortality following intracerebral hemorrhage (ICH) in two large population-based cohorts assembled more than a decade apart.

METHODS

All patients age > or = 18 hospitalized with nontraumatic ICH in the Greater Cincinnati/Northern Kentucky area were identified during 1988 (Cohort 1) and from May 1998 to July 2001 and August 2002 to April 2003 (Cohort 2). Mortality was tabulated using actuarial methods and compared with a log-rank test.

RESULTS

There were 183 patients with ICH in Cohort 1 and 1,041 patients in Cohort 2. Patients in Cohort 1 were more likely to be white (p = 0.024) and undergo operation for their ICH (p = 0.002), whereas patients in Cohort 2 were more commonly on anticoagulants (p < 0.001). Among patients in Cohort 1, mortality at 7 days, 1 year, and 10 years was 31, 59, and 82%. Among patients in Cohort 2, mortality at 7 days and 1 year was 34 and 53%. Mortality rates did not differ between cohorts by log-rank test (p = 0.259).

CONCLUSIONS

Intracerebral hemorrhage (ICH) mortality did not improve significantly between study periods. Operation for ICH became less frequent, whereas anticoagulant-associated ICH became more common.

Chronic chromium exposure-induced changes in testicular histoarchitecture are associated with oxidative stress: study in a non-human primate (Macaca radiata Geoffroy)

BACKGROUND

Reproductive toxicity of chromium is in dispute despite positive findings in rodents. Recently we reported epididymal toxicity of hexavalent chromium (CrVI) in bonnet monkeys and in this paper we report its testicular toxicity.

METHODS

Adult monkeys (Macaca radiata) were given drinking water containing CrVI (100, 200, 400 p.p.m.) for 6 months and testes were removed for ultrastructural and biochemical analyses.

RESULTS

CrVI treatment disrupted spermatogenesis, leading to accumulation of prematurely released spermatocytes, spermatids and uni- and multinucleate giant cells in the lumen of seminiferous tubules. Transmission electron microscopy revealed granulation of chromatin and vacuolation between acrosomal cap and manchette microtubules of elongated spermatids and in the Golgi area of round spermatids. Pachytene spermatocytes had fragmented chromatin and swollen mitochondria with collapsed cristae. Spermatocytes and spermatogonia in the basal compartment were unaffected. Macrophages containing phagocytosed sperm and dense inclusions in Sertoli cells were seen. Specific activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase and concentrations of the non-enzymatic antioxidants glutathione, vitamins A, C and E decreased, while concentrations of H(2)O(2) and hydroxyl radicals increased in the testis of chromium-treated monkeys. Withdrawal of chromium treatment for 6 months normalized spermatogenesis and the status of pro- and antioxidants in the testis.

CONCLUSIONS

CrVI disrupts spermatogenesis by inducing free radical toxicity, and supplementation of antioxidant vitamins may be beneficial to the affected subjects.

Chronic chromium exposure-induced changes in testicular histoarchitecture are associated with oxidative stress: study in a non-human primate (Macaca radiata Geoffroy)

BACKGROUND

Reproductive toxicity of chromium is in dispute despite positive findings in rodents. Recently we reported epididymal toxicity of hexavalent chromium (CrVI) in bonnet monkeys and in this paper we report its testicular toxicity.

METHODS

Adult monkeys (Macaca radiata) were given drinking water containing CrVI (100, 200, 400 p.p.m.) for 6 months and testes were removed for ultrastructural and biochemical analyses.

RESULTS

CrVI treatment disrupted spermatogenesis, leading to accumulation of prematurely released spermatocytes, spermatids and uni- and multinucleate giant cells in the lumen of seminiferous tubules. Transmission electron microscopy revealed granulation of chromatin and vacuolation between acrosomal cap and manchette microtubules of elongated spermatids and in the Golgi area of round spermatids. Pachytene spermatocytes had fragmented chromatin and swollen mitochondria with collapsed cristae. Spermatocytes and spermatogonia in the basal compartment were unaffected. Macrophages containing phagocytosed sperm and dense inclusions in Sertoli cells were seen. Specific activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase and concentrations of the non-enzymatic antioxidants glutathione, vitamins A, C and E decreased, while concentrations of H(2)O(2) and hydroxyl radicals increased in the testis of chromium-treated monkeys. Withdrawal of chromium treatment for 6 months normalized spermatogenesis and the status of pro- and antioxidants in the testis.

CONCLUSIONS

CrVI disrupts spermatogenesis by inducing free radical toxicity, and supplementation of antioxidant vitamins may be beneficial to the affected subjects.

Combined IV and intra-arterial thrombolysis for acute ischemic stroke

Combined IV and intra-arterial (IA) thrombolysis for acute ischemic stroke may offer advantages over either technique alone. Sixty-two nonrandomized patients with NIH Stroke Scale scores of > or =10 who met standard criteria for IV thrombolysis were treated with an IV/IA approach. Three-month modified Rankin Scale scores were 0 to 2 for 50% of patients, mortality was 18%, and symptomatic intracerebral hemorrhage occurred in 8%. IV/IA thrombolysis appeared safe and effective in this group.

Ten-year changes in smoking among young adults: are racial differences explained by socioeconomic factors in the CARDIA study?

OBJECTIVES

This study investigated whether socioeconomic factors explain racial/ethnic differences in regular smoking initiation and cessation.

METHODS

Data were derived from the CARDIA study, a cohort of 5115 healthy adults aged 18 to 30 years at baseline (1985-1986) and recruited from the populations of 4 US cities. Respondents were followed over 10 years.

RESULTS

Among 3950 respondents reexamined in 1995-1996, 20% of Whites and 33% of African Americans were smokers, as compared with 25% and 32%, respectively, in 1985-1986. On average, African Americans were of lower socioeconomic status. Ten-year regular smoking initiation rates for African American women, White women, African American men, and White men were 7.1%, 3.5%, 13.2%, and 5.1%, respectively, and the corresponding cessation rates were 25%, 35.1%, 19.2%, and 31.3%. After adjustment for socioeconomic factors, most 95% confidence intervals of the odds ratios for regular smoking initiation and cessation in African Americans vs Whites included 1.

CONCLUSIONS

Less beneficial 10-year changes in smoking were observed in African Americans, but socioeconomic factors explained most of the racial disparity.

Relation of race and sex to the use of reperfusion therapy in Medicare beneficiaries with acute myocardial infarction

BACKGROUND

There are few reports describing the combined influence of the race and sex of a patient on the use of reperfusion therapy for acute myocardial infarction.

METHODS

To determine the relation of race and sex to the receipt of reperfusion therapy for myocardial infarction in the United States, we reviewed the medical records of 234,769 Medicare patients with myocardial infarction. From these records we identified 26,575 white or black patients who met strict eligibility criteria for reperfusion therapy. We then performed bivariate and multivariate analyses of prevalence ratios to determine predictors of the use of reperfusion therapy in four subgroups of patients categorized according to race and sex: white men, white women, black men, and black women.

RESULTS

Among eligible patients, white men received reperfusion therapy with the highest frequency (59 percent), followed by white women (56 percent), black men (50 percent), and black women (44 percent). After adjustment for differences in demographic and clinical characteristics, white women were as likely as white men to receive reperfusion therapy (prevalence ratio, 1.00; 95 percent confidence interval, 0.98 to 1.03). Likewise, black women were as likely as black men to receive reperfusion therapy (prevalence ratio, 1.00; 95 percent confidence interval, 0.89 to 1.13). However, black women were significantly less likely to receive reperfusion therapy than white men (prevalence ratio, 0.90; 95 percent confidence interval, 0.82 to 0.98), as were black men (prevalence ratio, 0.85; 95 percent confidence interval, 0.78 to 0.93).

CONCLUSIONS

After adjustment for differences in clinical and demographic characteristics and clinical presentation, differences according to sex in the use of reperfusion therapy are minimal. However, blacks, regardless of sex, are significantly less likely than whites to receive this potentially lifesaving therapy.

Increased platelet activation and fibrinogen in Asian Indians. Potential implications for coronary risk

AIMS

To determine whether Asian Indians (Indians), a group known to have high rates of coronary heart disease, have increased platelet activation and fibrinogen levels relative to white Americans of European origin (whites).

METHODS AND RESULTS

Forty healthy, non-smoking Indians, aged 25-45, were matched with 40 healthy whites for age (within 3 years) and gender. Platelet activation was tested in blood exiting a bleeding time wound at 1 and 2 min post-incision (wound-induced activation), as well as in venous blood stimulated in vitro with collagen, using whole blood flow cytometry. Other risk factors, including fibrinogen levels, family history of diabetes or coronary heart disease, fasting insulin and lipid levels, and Lp(a) were also assessed. Fibrinogen levels were higher among Indians than whites, even after adjustment for gender or family history of coronary heart disease (P < 0.05). Indians had higher levels of wound-induced glycoprotein IIb/IIIa binding and platelet secretion (P-selectin expression) than whites, with the greatest differences found when comparing the upper quintile of activation for each group (Ps < 0.05). Indians with a family history of coronary heart disease (n = 15) had higher levels of platelet secretion (wound-induced and in vitro) than Indians without a family history (Ps < 0.05), while the relationship was reversed among whites. Platelet activation measures were not consistently related to other coronary risk factors, while fibrinogen was related to triglyceride and insulin levels among Indians.

CONCLUSION

Indians have elevated fibrinogen and platelet activation levels relative to whites. These factors may contribute to the increased coronary risk observed in Indians.

Comparison of long-term renal function after spinal cord injury using different urinary management methods

OBJECTIVE

To determine the effect of different bladder management methods on long-term renal function in persons with spinal cord injury (SCI).

DESIGN

Cohort study.

SETTING

Model SCI care system within a large teaching hospital.

PATIENTS

Consecutive sample of 1,114 persons with SCI who were injured between 1969 and 1994.

MAIN OUTCOME MEASURE

Total and individual kidney effective renal plasma flow (ERPF).

RESULTS

ERPF was generally lower in persons with cervical injuries or kidneys that had a renal stone, older persons, and women. Overall, there was very little change in renal function as time postinjury increased, and there were no clinically meaningful differences in the change in renal function over time among persons using different bladder management methods.

CONCLUSION

Renal function was adequately preserved in the great majority of persons and did not appear to be influenced to any great extent by method of bladder management.

Prevention of spinal cord injuries that occur in swimming pools

The purpose of this study was to determine the usual circumstances surrounding spinal cord injuries that occur in swimming pools so that appropriate primary prevention programs targeted at high risk persons, activities, and environments could be developed and initiated. A sample of 341 persons enrolled in the National Spinal Cord Injury Statistical Center database since 1973 whose injury was the result of a swimming pool mishap was identified. Medical records were reviewed retrospectively and a survey questionnaire was administered by telephone to 196 persons (57.5%) who were located and agreed to participate. Average age at time of injury was 24 years, 86% of injured persons were men, 95% were white, 70% were never married, 32% had less than a high school education, and only 7% were college graduates. Almost all injuries (87%) occurred in private/residential pools. Most injuries (57%) occurred when diving into less than 4 feet of water, while an additional 38% occurred at water depths between 4 and 8 feet. Depth indicators were not present in 75% of cases. There were no warning signs posted in 87% of cases. There was no lifeguard on duty in 94% of cases. There was self-reported alcohol involvement in 49% of cases, but drugs were involved in only 2% of cases. Almost half of all injuries (46%) occurred during parties. In 44% of cases, the injury occurred during the person's first visit to that particular pool. Ordinary dives accounted for 70% of cases, followed by unusual dives (17%), unintentional pushes (6%), and other circumstances (7%). Almost all injuries (88%) occurred between 1 pm and 1 am with the most frequent time of day being 6 pm, and 82% occurred during June, July or August. Over half (51%) of all injuries occurred on Saturday or Sunday. These results provide important clues to the development of a successful primary prevention program.

Effect of dexamethasone, 6-mercaptopurine and cyclosporine A on intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression

The expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) is increased in immune-mediated diseases. These adhesion molecules promote the adherence of inflammatory cells to parenchymal target cells. We have examined the effect of immunosuppressants on the expression of ICAM-1 and VCAM-1 in a renal tubular epithelial cell line. We found that dexamethasone (4-40 micrograms/mL), the azathioprine metabolite 6-mercaptopurine (10-100 micrograms/mL) and cyclosporine A (0.1-1 microgram/mL) have no effect on the basal and the tumor necrosis factor-alpha- or interleukin-1-stimulated expression of these adhesion molecules. We conclude that these immunosuppressants do not directly influence the expression of ICAM-1 and VCAM-1 by renal tubular epithelium.