Social Networks, Stigma, and Hepatitis C Care Among Women Who Inject Drugs: Findings from A Community Recruited Sample

This study explores the role of perceived HCV stigma and social networks on HCV care among people who inject drugs (PWID) of both sexes, and solely among women who inject drugs (WWID). Data were from 269 HCV positive PWID, community-recruited through street-based outreach in Baltimore, MD. We defined HCV stigma based on participants' perceptions of treatment by others and their need to conceal their HCV status. Among WWID, HCV stigma was linked with decreased odds of undergoing liver disease staging (aOR = 0.33, 95% CI: 0.13,0.85) or to have attempted to get the HCV cure (aOR = 0.39, CI: 0.16,0.97), these associations were not evident in the overall sample with both sexes. Social network characteristics were significant correlates of HCV care in the overall sample, and these associations were stronger among WWID. WWID with more HCV positive social network members had higher odds of an HCV-related healthcare visit in the prior 12 months (aOR = 4.28, CI: 1.29,14.17) and to have undergone liver disease staging (aOR = 2.85, CI: 1.01,8.05). WWID with more social network members aware of the HCV cure were more likely to report an attempt at obtaining the HCV cure (aOR = 5.25, CI: 1.85,14.89). Our results suggest complexity in the role of social networks and stigma on HCV care.

In light of breathing: environmental light is an important modulator of breathing with clinical implications

In vertebrate animals, the automatic, rhythmic pattern of breathing is a highly regulated process that can be modulated by various behavioral and physiological factors such as metabolism, sleep-wake state, activity level, and endocrine signaling. Environmental light influences many of these modulating factors both indirectly by organizing daily and seasonal rhythms of behavior and directly through acute changes in neural signaling. While several observations from rodent and human studies suggest that environmental light affects breathing, few have systematically evaluated the underlying mechanisms and clinical relevance of environmental light on the regulation of respiratory behavior. Here, we provide new evidence and discuss the potential neurobiological mechanisms by which light modulates breathing. We conclude that environmental light should be considered, from bench to bedside, as a clinically relevant modulator of respiratory health and disease.

Opioid and stimulant attributed treatment admissions and fatal overdoses: Using national surveillance data to examine the intersection of race, sex, and polysubstance use, 1992-2020

BACKGROUND

We use national surveillance data to evaluate race/ethnicity by sex/gender differences and trends in substance use treatment admissions and overdose deaths involving opioid and stimulant use.

METHODS

We used data (1992-2019) from the Treatment Episode Dataset-Admissions to identify treatment admissions and the Center for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research (1999-2020) to identify overdose deaths. We assessed treatment admissions and related drug overdose deaths per 100,000 adults by sex and race/ethnicity for opioid and stimulant groups: cocaine, opioid, methamphetamines, cocaine and opioid use, cocaine and methamphetamines, and opioid and methamphetamines.

RESULTS

We found significant variations in treatment admissions and deaths by race/ethnicity and sex/gender. Cocaine-related treatment admissions and deaths were most prevalent among Non-Hispanic Black individuals over the study years, yet lower rates were evident among individuals from other racial/ethnic groups. Notably, Non-Hispanic Black men experienced larger increases in cocaine-only admissions than men of other racial/ethnic groups between 1992 and 2019. Men had higher opioid and stimulant treatment admissions and overdose deaths than women. We observed skyrocketing methamphetamine deaths among American Indian/Native Alaskan men and women from 1992 to 2019.

DISCUSSION

Steep increases in overdose deaths fueled by methamphetamines among Non-Hispanic Native Americans and cocaine among Non-Hispanic Black individuals suggest a need for more effective interventions to curb stimulant use. Variations by race/ethnicity and sex/gender also suggest interventions should be developed through an intersectionality lens.

The Molecular Circadian Clock of Phox2b-expressing Cells Drives Daily Variation of the Hypoxic but Not Hypercapnic Ventilatory Response in Mice

While the suprachiasmatic nucleus (SCN) controls 24-h rhythms in breathing, including minute ventilation (V_E), the mechanisms by which the SCN drives these daily changes are not well understood. Moreover, the extent to which the circadian clock regulates hypercapnic and hypoxic ventilatory chemoreflexes is unknown. We hypothesized that the SCN regulates daily breathing and chemoreflex rhythms by synchronizing the molecular circadian clock of cells. We used whole-body plethysmography to assess ventilatory function in transgenic BMAL1 knockout (KO) mice to determine the role of the molecular clock in regulating daily rhythms in ventilation and chemoreflex. Unlike their wild-type littermates, BMAL1 KO mice exhibited a blunted daily rhythm in V_E and failed to demonstrate daily variation in the hypoxic ventilatory response (HVR) or hypercapnic ventilatory response (HCVR). To determine if the observed phenotype was mediated by the molecular clock of key respiratory cells, we then assessed ventilatory rhythms in BMAL1^fl/fl; Phox2b^Cre/+ mice, which lack BMAL1 in all Phox2b-expressing chemoreceptor cells (hereafter called BKOP). BKOP mice lacked daily variation in HVR, similar to BMAL1 KO mice. However, unlike BMAL1 KO mice, BKOP mice exhibited circadian variations in V_E and HCVR comparable to controls. These data indicate that the SCN regulates daily rhythms in V_E, HVR, and HCVR, in part, through the synchronization of the molecular clock. Moreover, the molecular clock of Phox2b-expressing cells is specifically necessary for daily variation in the hypoxic chemoreflex. These findings suggest that disruption of circadian biology may undermine respiratory homeostasis, which, in turn, may have clinical implications for respiratory disease.

Daily opioid and stimulant co-use and nonfatal overdoses in the context of social disadvantage: Findings on marginalized populations

OBJECTIVE

Opioids and stimulants are increasingly implicated in overdose deaths, particularly among minoritized groups. We examined daily opioid and cocaine co-use, nonfatal overdoses, and naloxone carrying among minoritized people who inject drugs (PWID).

METHODS

The study derived data from 499 PWID in Baltimore City, MD, recruited using street-based outreach between 2016 and 2019. Participants reported overdoses; sociodemographic characteristics; and use of nonmedical prescription opioids, heroin, cocaine, and naloxone.

RESULTS

Among the participants, the mean age was 46, 34 % were female, 64 % self-identified as Black, and 53 % experienced recent homelessness. Black PWID, compared to White PWID, were as likely to use opioids and cocaine daily but were 61 % less likely to have naloxone. After controlling for sociodemographic characteristics, women (aOR:1.88, 95%CI: 1.14, 3.11), persons experiencing homelessness (aOR:3.07, 95%CI: 1.79, 5.24), and those who experienced a recent overdose (aOR:2.14, 95%CI: 1.29, 3.58) were significantly more likely to use opioids and any form of cocaine every day. In a subanalysis of only female PWID, females engaged in sex work (aOR:2.27, 95%CI: 1.02, 5.07) and females experiencing recent homelessness (aOR:5.82, 95%CI: 2.50, 13.52) were significantly more likely to use opioids and cocaine daily. Furthermore, females (aOR:1.69, 95%CI:1.03, 2.77), persons experiencing homelessness (aOR:1.94, 95%CI:1.16, 3.24), and those with higher educational attainment (aOR:2.06, 95%CI:1.09, 3.91) were more likely to often/always carry naloxone, while Black PWID were less likely to have naloxone (aOR:0.39, 95%CI:0.22, 0.69).

CONCLUSIONS

These findings highlight the need for targeted naloxone distribution and other harm-reduction interventions among minoritized groups in urban areas.

Caloric restriction prevents obesity- and intermittent hypoxia-induced cardiac remodeling in leptin-deficient ob/ob mice

Background: Intermittent hypoxia (IH), a key characteristic of obstructive sleep apnea, is independently associated with cardiometabolic impairment. While endogenous leptin levels may provide cardioprotective effects against hypoxia, leptin resistance is common among obese individuals presenting with obstructive sleep apnea.

Methods: Here, we assessed left ventricle (LV) function using M-mode echocardiography in lean wild-type, calorically-restricted ob/ob, and obese ob/ob mice before and after 6 days of IH to determine how obesity and intermittent hypoxia interact to affect cardiac function independent of leptin signaling.

Results: Calorically-restricting ob/ob mice for 4 weeks prior to IH exposure prevented weight gain (−2.1 ± 1.4 g) compared to free-fed ob/ob mice (8.7 ± 1.1 g). Free-fed ob/ob mice exhibited increased LV mass (0.713 ± 0.008 g) relative to wild-type mice (0.685 ± 0.004 g) and increased posterior wall thickness (0.089 ± 0.006 cm) relative to calorically-restricted ob/ob mice (0.072 ± 0.004 cm). Following 6 days of IH, free-fed ob/ob mice exhibited increases in cardiac output (44.81 ± 2.97 pre-IH vs. 57.14 ± 3.09 ml/min post-IH), LV diameter (0.400 ± 0.007 pre-IH vs. 0.428 ± 0.009 cm post-IH) and end diastolic volume (0.160 ± 0.007 pre-IH vs. 0.195 ± 0.012 ml post-IH) that were not detected in wild-type or calorically-restricted ob/ob mice.

Conclusion: Caloric restriction can prevent obesity-induced LV hypertrophy and protect against acute IH-induced cardiac remodeling independent of leptin signaling. These findings may have clinical implications for obstructive sleep apnea.

The timing of intermittent hypoxia differentially affects macronutrient intake and energy substrate utilization in mice

Sleep apnea is a common sleep disorder characterized by periodic breathing cessation and intermittent hypoxia (IH). Although previous studies have demonstrated that IH alone can influence metabolic outcomes such as body weight, it remains unclear how the timing of IH can specifically affect these outcomes. Here, we examine how pairing 10-h periods of IH to either the animals' resting phase (e.g., IH during the day) or active phase (e.g., IH during the night) differentially affects body weight, macronutrient selection, energy expenditure, respiratory exchange rate, and glucose tolerance. We find that in contrast to mice exposed to IH during the night, mice exposed to IH during the day preferentially decrease their carbohydrate intake and switch to fat metabolism. Moreover, when the IH stimulus was removed, mice that had been exposed to day IH continued to eat a minimal amount of carbohydrates and consumed a higher percentage of kilocalorie from fat for at least 5 days. These data demonstrate that food choice and substrate utilization are secondary to the timing of IH but not IH itself. Taken together, these data have key clinical implications for individuals with sleep apnea and particularly those who are also experiencing circadian disruption such as night-shift workers.NEW & NOTEWORTHY Pairing repeated hypoxic episodes to a mouse's resting phase during the day preferentially decreases carbohydrate intake and results in a switch to metabolic fat oxidation. These data indicate that the timing of intermittent hypoxia should be considered when calculating sleep apnea's effects on metabolic outcomes.

Racial differences in overdose training, naloxone possession, and naloxone administration among clients and nonclients of a syringe services program

OBJECTIVE

To evaluate racial (Black/White) differences in overdose response training and take-home naloxone (THN) possession and administration among clients and nonclients of the Baltimore syringe service program (SSP).

METHODS

The study derived data from a cross-sectional survey of 263 (183 SSP clients, 80 nonclients) people who inject drugs (PWID). The study recruited SSP clients using targeted sampling and recruited nonclients through peer referral from April to November 2016.

RESULTS

In our sample, 61% of the participants were Black, 42% were between the ages of 18 and 44, and 70% were males. SSP clients, regardless of race, were more likely to have received overdose response training than Black nonclients (Black clients AOR: 3.85, 95% CI: 1.88, 7.92; White clients AOR: 2.73, 95% CI: 1.29, 5.75). The study found no significant differences in overdose response training between Black and White nonclients. SSP clients and White nonclients were more likely to possess THN than Black nonclients (Black clients: AOR: 4.21, 95% CI: 2.00, 8.87; White clients: AOR: 3.54, 95% CI: 1.56, 8.04; White nonclients AOR: 4.49, 95% CI: 1.50,13.47).

CONCLUSION

SSP clients were more likely to receive overdose response training than their nonclient peers who they referred to the study, illustrating the utility of SSPs in reaching PWID at high risk of overdose. We also observed that Black PWID, who did not access services at the SSP, were the least likely to possess THN, suggesting the need to employ outreach targeting Black PWID who do not access this central harm reduction intervention.

Acacetin and Pinostrobin Inhibit Malignant Breast Epithelial Cell Adhesion and Focal Adhesion Formation to Attenuate Cell Migration

Naturally occurring flavonoids, such as acacetin and pinostrobin, disrupt a wide range of processes during tumor progression, such as cell proliferation, apoptosis, and angiogenesis. Although the antiproliferative and antiapoptotic effects of acacetin and pinostrobin have been studied using various cell lines, relatively little is known about the effects of acacetin and pinostrobin on cancer cell migration and metastasis. For instance, it is unclear whether acacetin or pinostrobin have any effect on breast cancer cell migration or adhesion. In this study, we assessed the effects of acacetin and pinostrobin on malignant MDA-MB-231 and T47D breast epithelial cells and non-tumorigenic MCF10A breast epithelial cells. Our results demonstrate that both acacetin and pinostrobin selectively inhibit the migration of both MDA-MB-231 and T47D cells in a dose-dependent manner while exhibiting blunted effects on MCF10A cells. Interestingly, neither compound had an effect on cell proliferation in any of the 3 cell lines. Furthermore, both acacetin and pinostrobin inhibit MDA-MB-231 and T47D cell adhesion, cell spreading, and focal adhesion formation, but have no significant effect on MCF10A cells. Collectively, these results suggest that both acacetin and pinostrobin selectively inhibit malignant breast epithelial cell migration through attenuation of cell adhesion and focal adhesion formation. These findings indicate that both acacetin and pinostrobin may serve as potential therapeutic options to target breast tumor cell migration during late-stage tumor progression.

Proteomic study of Desulfovibrio ferrophilus IS5 reveals overexpressed extracellular multi-heme cytochrome associated with severe microbiologically influenced corrosion

Microbiologically influenced corrosion (MIC) is recognized as a considerable threat to carbon steel asset integrity in the oil and gas industry. There is an immediate need for reliable and broadly applicable methods for detection and monitoring of MIC. Proteins associated with microbial metabolisms involved in MIC could serve as useful biomarkers for MIC diagnosis and monitoring. A proteomic study was conducted using a lithotrophically-grown bacterium Desulfovibrio ferrophilus strain IS5, which is known to cause severe MIC in seawater environments. Unique proteins, which are differentially and uniquely expressed during severe microbial corrosion by strain IS5, were identified. This includes the detection of a multi-heme cytochrome protein possibly involved in extracellular electron transfer in the presence of the carbon steel. Thus, we conclude that this newly identified protein associated closely with severe MIC could be used to generate easy-to-implement immunoassays for reliable detection of microbiological corrosion in the field.

Photoperiod Manipulation Reveals a Light-Driven Component to Daily Patterns of Ventilation in Male C57Bl/6J Mice

Obstructive sleep apnea is a common sleep disorder that increases risk for cardiovascular disease and mortality. The severity of sleep-disordered breathing in obstructive sleep apnea patients fluctuates with the seasons, opening the possibility that seasonal changes in light duration, or photoperiod, can influence mechanisms of breathing. Photoperiod can have profound effects on internal timekeeping and can reshape metabolic rhythms in mammals. While the daily rhythm in ventilation is largely shaped by the metabolic rate, less is known about whether ventilatory rhythms are altered in accordance with metabolism under different photoperiods. Here, we investigate the relationship between ventilation and metabolism under different photoperiods using whole-body plethysmography and indirect calorimetry. We find that the daily timing of ventilation is chiefly synchronized to dark onset and that light cues are important for maintaining daily ventilatory rhythms. Moreover, changes in ventilatory patterns are not paralleled by changes in oxygen consumption, energy expenditure, or respiratory exchange rate under different photoperiods. We conclude that ventilatory patterns are not only shaped by the metabolic rate and circadian timing but are also influenced by other light-driven factors. Collectively, these findings have clinical implications for the seasonal variations in sleep-disordered breathing found in individuals with obstructive sleep apnea.

Responses to the Hydrostatic Pressure of Surface and Subsurface Strains of Pseudothermotoga elfii Revealing the Piezophilic Nature of the Strain Originating From an Oil-Producing Well

Microorganisms living in deep-oil reservoirs face extreme conditions of elevated temperature and hydrostatic pressure. Within these microbial communities, members of the order Thermotogales are predominant. Among them, the genus Pseudothermotoga is widespread in oilfield-produced waters. The growth and cell phenotypes under hydrostatic pressures ranging from 0.1 to 50 MPa of two strains from the same species originating from subsurface, Pseudothermotoga elfii DSM9442 isolated from a deep African oil-producing well, and surface, P. elfii subsp. lettingae isolated from a thermophilic sulfate-reducing bioreactor, environments are reported for the first time. The data support evidence for the piezophilic nature of P. elfii DSM9442, with an optimal hydrostatic pressure for growth of 20 MPa and an upper limit of 40 MPa, and the piezotolerance of P. elfii subsp. lettingae with growth occurring up to 20 MPa only. Under the experimental conditions, both strains produce mostly acetate and propionate as volatile fatty acids with slight variations with respect to the hydrostatic pressure for P. elfii DSM9442. The data show that the metabolism of P. elfii DSM9442 is optimized when grown at 20 MPa, in agreement with its piezophilic nature. Both Pseudothermotoga strains form chained cells when the hydrostatic pressure increases, especially P. elfii DSM9442 for which 44% of cells is chained when grown at 40 MPa. The viability of the chained cells increases with the increase in the hydrostatic pressure, indicating that chain formation is a protective mechanism for P. elfii DSM9442.

Mineral Ecology: Surface Specific Colonization and Geochemical Drivers of Biofilm Accumulation, Composition, and Phylogeny

This study tests the hypothesis that surface composition influences microbial community structure and growth of biofilms. We used laboratory biofilm reactors (inoculated with a diverse subsurface community) to explore the phylogenetic and taxonomic variability in microbial communities as a function of surface type (carbonate, silicate, aluminosilicate), media pH, and carbon and phosphate availability. Using high-throughput pyrosequencing, we found that surface type significantly controlled ~70–90% of the variance in phylogenetic diversity regardless of environmental pressures. Consistent patterns also emerged in the taxonomy of specific guilds (sulfur-oxidizers/reducers, Gram-positives, acidophiles) due to variations in media chemistry. Media phosphate availability was a key property associated with variation in phylogeny and taxonomy of whole reactors and was negatively correlated with biofilm accumulation and α-diversity (species richness and evenness). However, mineral-bound phosphate limitations were correlated with less biofilm. Carbon added to the media was correlated with a significant increase in biofilm accumulation and overall α-diversity. Additionally, planktonic communities were phylogenetically distant from those in biofilms. All treatments harbored structurally (taxonomically and phylogenetically) distinct microbial communities. Selective advantages within each treatment encouraged growth and revealed the presence of hundreds of additional operational taxonomix units (OTU), representing distinct consortiums of microorganisms. Ultimately, these results provide evidence that mineral/rock composition significantly influences microbial community structure, diversity, membership, phylogenetic variability, and biofilm growth in subsurface communities.

Mapping loss of heterozygosity in normal human breast cells from BRCA1/2 carriers

We have studied loss of heterozygosity at the BRCA1 and BRCA2 loci in 992 normal cell clones derived from topographically defined areas of normal tissue in four samples from BRCA1/BRCA2 mutation carriers. The frequency of loss of heterozygosity in the clones was low (1.01%), but it was found in all four samples, whether or not a tumour was present. Topographical mapping revealed that the genetic changes were clustered in some breast samples. Our study confirms the previous finding that a field of genetic instability can exist around a tumour, suggesting that sufficient tissue must be removed at surgery to avoid local recurrence. We also demonstrate that such a field of genetic change can exist in morphologically normal tissue before a tumour develops and, for the first time, we demonstrate that the field is of a size greater than one terminal duct-lobular unit. The genetic changes are not identical, however, which suggests that genetic instability in these regions may play an early role in tumour development. We also confirm and extend our original observation of loss of the wild-type BRCA1 allele in some clones, and loss of the mutant allele in others, demonstrating that loss of either allele is a stochastic event.

Evaluation of recombinant human bone morphogenetic protein-2 in oral applications including the use of endosseous implants: 3-year results of a pilot study in humans

BACKGROUND

This study evaluated patients who had been treated with recombinant human bone morphogenetic protein-2 (rhBMP-2) loaded in an absorbable collagen sponge (ACS) in human extraction sites or in sites that required alveolar ridge augmentation. An earlier report on the same patients revealed that after 4 months, implantation of rhBMP-2/ACS was safe, as determined by clinical, radiographic, systemic, and immunological analyses. In this longer-term follow-up, eligible patients were restored with endosseous dental implants in the area treated with rhBMP-2/ACS and bone biopsy samples were taken for histological analysis of the treated human bone tissue. The primary objective was to monitor the long-term safety of patients treated with rhBMP-2/ACS. Another objective was to evaluate the dental implants placed in the sites treated with rhBMP-2.

METHODS

Patient safety was evaluated by clinical examinations, periapical radiographs, and occurrence of adverse experiences. Dental implants were evaluated by radiographic and clinical examination. All 12 patients have been followed for 3 years.

RESULTS

Two years following surgical implantation of rhBMP-2/ACS, no serious or unexpected adverse experiences occurred. The adverse experiences that did occur were mostly benign and compatible with the dental implant surgeries performed in these patients. No adverse experiences were deemed as related to the rhBMP-2/ACS. Furthermore, no safety concerns in the local area of rhBMP-2/ACS placement were noted, based on oral wound examinations. In the 10 patients (6 extraction socket patients and 4 augmentation patients) who received endosseous implants, all implants were clinically stable at all assessments and all 10 patients have been functionally restored. Histological evaluation of the human bone core biopsies revealed normal bone tissue formation identical to the surrounding native bone. Three-year follow-up clinical examinations revealed that all implants had stable marginal bone levels and healthy peri-implant tissues.

CONCLUSIONS

These 3-year results demonstrate that rhBMP-2/ACS can be used safely in human patients. Human bone biopsies reveal normal bone formation in areas treated with rhBMP-2/ACS. Endosseous implants placed in these areas were all stable with no radiographic or clinical complications. The results from this study suggest that rhBMP-2/ACS (0.43 mg/ml) can be safely used in tooth extraction sites and in local ridge augmentation procedures and that endosseous dental implants placed in bony areas treated with rhBMP-2/ACS are stable and can be functionally restored without complication.

Volunteer services for vulnerable families and at-risk elderly

OBJECTIVE

The purpose of this paper is to explore the role of the volunteer with vulnerable populations, specifically, new parents and their infants and at-risk elderly. As demand for volunteer services increases due to budgetary and personnel reductions, a better understanding of volunteers as service providers is imperative.

METHOD

A review of the literature related to volunteers who work with these two populations was conducted. Volunteer characteristics, roles, needs of populations served, recruitment, and training issues were addressed, specifically as they relate to the two populations.

RESULTS

Studies indicate that the socio-demographic range of volunteers is wide, as are the motivations for volunteering. Similarities between the needs of new families and the elderly exist, and volunteers for both populations often provide supportive and pragmatic services. Volunteers for both populations are further challenged to maintain a client-focused intervention, a task which may be more difficult in the home. Training of volunteers was found to be both client and volunteer driven, with the needs of the population being served and the role of the volunteer within a specific service domain of prime importance.

CONCLUSION

Similarities between infant and elder populations exist, as do volunteer interventions with these populations. A theoretical framework for defining motivation, designing need-based training, and addressing the role of volunteers is discussed. The use of volunteers as compassionate and cost-effective service providers for populations across the lifespan not only provides an increase in the number of skilled workers involved with these vulnerable populations, but also allows professional staff to expand the care which they are able to provide.

Linking lost voices: reading 'The Dead'

The author presents an individual reading of James Joyce's short story. 'The Dead' from 'Dubliners'. Language evokes subjective responses and associations that become part of the depth of experience one finds in a book. The author describes how uses of language give the reader a sense of sharing the main character's experience. She focuses on nodal moments in the story, in which external and internal worlds intersect. Images focused on include those of seeing and touching, inside and outside, crossing gaps between worlds and the way in which these sensory events shift the character's knowledge of his internal objects. The metaphor of lost voices highlights the presence of the dead throughout the story. The main character's evolution from being in a constricted state to one of expanded self-awareness is discussed. Britton's concept of triangular space is used to describe the character's transformation at the story's conclusion.

Recombinant human bone morphogenetic protein-2 stimulation of bone formation around endosseous dental implants

BACKGROUND

Successful endosseous implant placement requires that the implant be stable in alveolar bone. In certain cases, the implant can be stabilized in native bone but some part of the implant is not covered by bone tissue. This often occurs during placement of implants into extraction sites or in areas where bone resorption has occurred and the ridge width is not sufficient to completely surround the implant. In those cases, the clinician usually employs a procedure to encourage bone formation. These procedures typically include a bone graft and/or membrane therapy. Recent advances have led to the isolation, cloning, and production of recombinant human proteins that stimulate bone formation. One of these bone morphogenetic proteins (rhBMP-2) has been extensively studied in animal models and is currently being tested in human clinical trials.

METHODS

In this study, rhBMP-2 was tested using a collagen sponge carrier to stimulate bone formation in defects in the canine mandible around endosseous dental implants. Six animals had a total of 48 implants placed. rhBMP-2 with the collagen carrier was implanted around 24 of these, the remainder having only the collagen carrier placed. Half the sites were covered with a nonresorbable expanded polytetrafluoroethylene membrane. Histologic analysis was performed after 4 and 12 weeks. The area of new bone formed, percentage of bone-to-implant contact in the defect area, and percentage fill of the defect was calculated.

RESULTS

The addition of rhBMP-2 resulted in significantly greater amounts of new bone area and percentage of bone-to-implant contact and with more percentage fill after 4 and 12 weeks of healing. The area of new bone formed was reduced after 4 weeks when a membrane was present but after 12 weeks, there was no significant difference between membrane and non-membrane treated sites. In some specimens, new bone was found coronal to the membranes, with rhBMP-2-treated sites having greater amounts than non-rhBMP-2-treated sites.

CONCLUSIONS

These data demonstrate that a bone differentiation factor significantly stimulates bone formation in peri-implant bone defects in the canine mandible. In addition, bone-to-implant contact was significantly enhanced along the rough implant surface. Membrane-treated sites had less new bone formation after 4 weeks of healing but were similar to non-membrane sites after 12 weeks. These results demonstrate that rhBMP-2 can be used to stimulate bone growth both around and onto the surface of endosseous dental implants placed in sites with extended peri-implant osseous defects.

A 129Xe NMR study on an ionomeric polymer blend system

The morphology of an ionomeric polymer blend consisting of an amino-silicone copolymer and zinc neutralized sulfonated polystyrene (ZnSPS) has been studied using proton spin diffusion and small angle X-ray scattering (SAXS). The extent of reaction between the two components in the blend was monitored by 13C CP MAS spectroscopy. All three types of experiment point to domain sizes in the nanometer range. 129Xe NMR was used to study exchange by translational diffusion between domains. A single xenon resonance was detected in temperatures ranging from 25 degrees C to -90 degrees C, and the chemical shift followed a weighted average of the isolated polymer shifts consistent with the small domain sizes. Pulse field gradient 129Xe NMR was used to determine the effective diffusion constants in the amino silicone starting material and the blend. The diffusion constant of xenon in poly(styrene) is known, allowing for comparison of the predictions of effective diffusion constants in the blend based on the values in the constituents of the blend. Simple two-site exchange equations incorrectly predict that diffusion in the blend would be dominated by the constituent with slow diffusion. The blend diffusion constant is close to the value of the amino silicone or the constituent with fast diffusion which is correctly predicted for a rapid exchange solution of the diffusion equation.

Clinical evaluation of bioactive glass in the treatment of periodontal osseous defects in humans

The purpose of this study was to compare the use of bioactive glass to demineralized freeze-dried bone allograft (DFDBA) in the treatment of human periodontal osseous defects. Fifteen systemically healthy patients (6 males and 9 females, aged 30 to 63) with moderate to advanced adult periodontitis were selected for the study. All patients underwent initial therapy, which included scaling and root planing, oral hygiene instruction, and an occlusal adjustment when indicated, followed by re-evaluation 4 to 6 weeks later. Paired osseous defects in each subject were randomly selected to receive grafts of bioactive glass or DFDBA. Both soft and hard tissue measurements were taken the day of surgery (baseline) and at the 6-month re-entry surgery. The clinical examiner was calibrated and blinded to the surgical procedures, while the surgeon was masked to the clinical measurements. Statistical analysis was performed by using the paired Student's t test. The results indicated that probing depths were reduced by 3.07 +/- 0.80 mm with the bioactive glass and 2.60 +/- 1.40 mm with DFDBA. Sites grafted with bioactive glass resulted in 2.27 +/- 0.88 mm attachment level gain, while sites grafted with DFDBA had a 1.93 +/- 1.33 mm gain in attachment. Bioactive glass sites displayed 0.53 +/- 0.64 mm of crestal resorption and 2.73 mm bone fill. DFDBA-grafted sites experienced 0.80 +/- 0.56 mm of crestal resorption and 2.80 mm defect fill. The use of bioactive glass resulted in 61.8% bone fill and 73.33% defect resolution. DFDBA-grafted defects showed similar results, with 62.5% bone fill and 80.87% defect resolution. Both treatments provided soft and hard tissue improvements when compared to baseline (P < or = 0.0001). No statistical difference was found when comparing bioactive glass to DFDBA; however, studies with larger sample sizes may reveal true differences between the materials. This study suggests that bioactive glass is capable of producing results in the short term (6 months) similar to that of DFDBA when used in moderate to deep intrabony periodontal defects.

Randomized, placebo-controlled trial of platelet glycoprotein IIb/IIIa blockade with primary angioplasty for acute myocardial infarction. ReoPro and Primary PTCA Organization and Randomized Trial (RAPPORT) Investigators

BACKGROUND

The benefit of catheter-based reperfusion for acute myocardial infarction (MI) is limited by a 5% to 15% incidence of in-hospital major ischemic events, usually caused by infarct artery reocclusion, and a 20% to 40% need for repeat percutaneous or surgical revascularization. Platelets play a key role in the process of early infarct artery reocclusion, but inhibition of aggregation via the glycoprotein IIb/IIIa receptor has not been prospectively evaluated in the setting of acute MI.

METHODS AND RESULTS

Patients with acute MI of <12 hours' duration were randomized, on a double-blind basis, to placebo or abciximab if they were deemed candidates for primary PTCA. The primary efficacy end point was death, reinfarction, or any (urgent or elective) target vessel revascularization (TVR) at 6 months by intention-to-treat (ITT) analysis. Other key prespecified end points were early (7 and 30 days) death, reinfarction, or urgent TVR. The baseline clinical and angiographic variables of the 483 (242 placebo and 241 abciximab) patients were balanced. There was no difference in the incidence of the primary 6-month end point (ITT analysis) in the 2 groups (28.1% and 28.2%, P=0.97, of the placebo and abciximab patients, respectively). However, abciximab significantly reduced the incidence of death, reinfarction, or urgent TVR at all time points assessed (9.9% versus 3.3%, P=0.003, at 7 days; 11.2% versus 5.8%, P=0.03, at 30 days; and 17.8% versus 11.6%, P=0.05, at 6 months). Analysis by actual treatment with PTCA and study drug demonstrated a considerable effect of abciximab with respect to death or reinfarction: 4.7% versus 1.4%, P=0.047, at 7 days; 5.8% versus 3.2%, P=0.20, at 30 days; and 12.0% versus 6.9%, P=0.07, at 6 months. The need for unplanned, "bail-out" stenting was reduced by 42% in the abciximab group (20.4% versus 11.9%, P=0.008). Major bleeding occurred significantly more frequently in the abciximab group (16.6% versus 9.5%, P=0.02), mostly at the arterial access site. There was no intracranial hemorrhage in either group.

CONCLUSIONS

Aggressive platelet inhibition with abciximab during primary PTCA for acute MI yielded a substantial reduction in the acute (30-day) phase for death, reinfarction, and urgent target vessel revascularization. However, the bleeding rates were excessive, and the 6-month primary end point, which included elective revascularization, was not favorably affected.

Risk of blood contamination of health care workers in spine surgery. A study of 324 cases

STUDY DESIGN

The relative risk of blood contamination during spine surgery was studied using data collected from 324 procedures.

OBJECTIVES

To analyze demographic factors that predict blood-borne pathogens in the population of spine surgery patients, study the rates and patterns of blood contamination in health care workers (i.e., skin-penetrating incidents and nonpenetrating surface skin contamination from patients' blood) and compare those risks with those in other surgical departments, and analyze the effectiveness of barrier systems worn by the surgical team.

SUMMARY OF BACKGROUND DATA

The Centers for Disease Control and Prevention has reported 49 health care workers infected by the human immunodeficiency virus through occupational exposure. Several studies have noted the risk of blood contamination in various surgical departments, but the relative risk during spine surgery has not been determined.

METHODS

This year-long survey included 9795 cases, or 60,789 health care worker--patient contacts, of which spine disorders comprised 324 cases (2234 health care workers and patients). Data collection forms were designed and inservice training conducted with operating room staffs. Information regarding type of case, staff position (surgeon, assistant, scrub nurse, circulator), protective clothing worn, length of operating room time, blood loss, incidence of blood spills, was recorded, among other data.

RESULTS

Prevalence of human immunodeficiency virus in patients in the overall series was 0.19% versus 0.93% in spine patients. The rate of HCW contamination in the overall series was 7.76%, of which 0.92% resulted from skin-penetrating incidents. Contamination in spine surgery occurred in 31.86% of cases, of which 1.23% were the result of skin-penetrating incidents.

CONCLUSIONS

Health care workers in spine surgery have a statistically significant overall higher risk of blood contamination than do those in other surgical departments. The increased risk occurred with blood contacting intact skin. There was no higher risk for skin penetrating injury. Analysis of data suggests that health care workers always should wear double gloves, forearm-reinforced gowns, and eye protection.

Copper supplementation of adult men: effects on blood copper enzyme activities and indicators of cardiovascular disease risk

In rats, copper deficiency leads to low copper metalloenzyme activity, high serum cholesterol, and cardiovascular lesions. In humans, moderately low copper intake may be common, but the consequences remain largely uncertain. The present study examined the effects of copper supplementation (2 mg/d for 4 weeks in a copper/placebo crossover design) in 20 adult men with moderately high plasma cholesterol. End-point measurements were three copper enzyme activities, erythrocyte superoxide dismutase (SOD), plasma ceruloplasmin (Cp), and plasma diamine oxidase (DAO), and three parameters related to the risk of cardiovascular disease (CVD), plasma cholesterol, plasma lipoprotein (a) [Lp(a)], and lag times for very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) oxidation in vitro. Although copper had no significant effects on any parameter for the entire study group, it did significantly increase two enzyme activities (SOD and DAO), as well as lipoprotein oxidation lag times, in 10 subjects in the lower half of a median split for precopper values. Thus, copper supplementation appeared to influence some types of measurements in subjects beginning with less than median values.

Radiographic analysis of regenerated bone around endosseous implants in the canine using recombinant human bone morphogenetic protein-2

Ideal endosseous implant placement involves a congruent bony housing in close apposition to the implant surface. Clinical situations are encountered, however, in which the entire implant surface cannot be in close apposition to bone. In these instances, bone grafting materials are generally used to regenerate bone around the implant. In this study, a biologically active bone differentiation factor, recombinant human bone morphogenetic protein-2 (rhBMP-2), was used with two different carriers to regenerate bone around implants in standardized critical-sized defects in the canine mandible. Half of the sites had a nonresorbable membrane placed over the defect. Longitudinal standardized radiographs were obtained to assess the amount of bone regeneration on the mesial and distal of the implants after 4 and 12 weeks of healing. Ninety-six implants were placed in 12 fox-hounds. Bone fill was determined by linear measurement of bone on the radiographs, and changes in bone density were evaluated by computer-assisted densitometric image analysis of discrete areas adjacent to the implant. After 4 weeks of healing, nonmembrane sites had significantly greater bone height than membrane-protected sites. Following 12 weeks of healing, sites treated with rhBMP-2 had significantly greater bone formation than untreated sites. Sites treated with rhBMP-2 and a membrane had the greatest bone fill, followed by sites treated with rhBMP-2 but no membrane. Sites without rhBMP-2, whether with or without a membrane, had less bone fill than sites with rhBMP-2. At 12 weeks, sites with a membrane resulted in significantly more gain in bone density than sites without a membrane. Furthermore, sites treated with a collagen carrier resulted in greater gains in bone density than sites treated with a polylactide/glycolide carrier. The results from this study demonstrate by radiographic evidence that new bone formation in critical-sized defects around implants is dependent on time after defect treatment, the type of carrier used, the use of a barrier membrane, and the presence of rhBMP-2. In addition, these findings suggest that rhBMP-2, a bone differentiation factor, can significantly stimulate bone formation around endosseous dental implants.

Experiencing language: some thoughts on poetry and psychoanalysis

The author uses her experiences as a poet and as a psychoanalyst to compare the two. She discusses poems by James Merrill, Philip Larkin, and Theodore Roethke in order to consider how the analyst listens, how the poet writes, how each listens to what is unsaid in the music of language. Rhythm, meter, and the sounds of words constitute this music. Sound and image are means by which language bypasses logic and touches us. Considering how a poem has an impact can teach us something about how words affect us in psychoanalysis.

Plasma diamine oxidase activities in renal dialysis patients, a human with spontaneous copper deficiency and marginally copper deficient rats

OBJECTIVES

Intestine and kidney are generally the most concentrated sources of the copper metalloenzyme diamine oxidase (DAO). Clinically, plasma DAO activities are used to diagnose disruptions in intestinal integrity. This study determined whether DAO activities were also affected by kidney injury or copper nutritional status.

DESIGN AND METHODS

Plasma DAO activities were measured in renal dialysis patients without diagnosed intestinal disease (n = 75), controls (n = 23), an adult with spontaneous copper deficiency before and after copper repletions, and in rats fed either adequate or marginal copper diets (8 or 2 mg copper/kg diet) for 7 months.

RESULTS

This study found high DAO activities in renal dialysis patients and low activities during spontaneous copper deficiency. Low activities were also seen for marginally copper deficient rats.

CONCLUSIONS

Tissue injury-induced elevation of DAO activities is not limited to intestinal injury, and low DAO values may be useful for assessing copper nutritional status.

Suspected neonatal isoerythrolysis in two Baird's tapirs (Tapirus bairdii)

Two Baird's tapir (Tapirus bairdii) calves born at the Columbus Zoo from the same sire and dam developed hemolytic anemia that was consistent in history and clinical signs with neonatal isoerythrolysis (NI). One calf developed severe, fatal hemolytic anemia after being fed maternal colostrum, and the other developed moderate hemolytic anemia after being fed equine colostrum. No cross-reactivity was demonstrated between sire and dam blood samples, and both tapirs possessed serum antibodies reactive against equine blood group Ca and antigens reactive with several equine blood group D antibodies. Electrophoresis demonstrated significant genetic diversity between tapir and equine blood proteins. Agglutination testing demonstrated strong reactivity between a far greater percentage of equine colostrum samples when tested against sire and dam tapir blood (61% and 65%, respectively) than would be expected for equine blood (2%). These data are suggestive of a diagnosis of NI but are not definitive. Further study is required to determine whether NI occurs in tapirs and whether equine colostrum is harmful to tapir calves.

High ceruloplasmin levels in rats without high lipoprotein oxidation rates

The serum copper protein ceruloplasmin, though sometimes considered an antioxidant, can promote lipoprotein oxidation in vitro under certain conditions. However, an inflammation-induced, two week elevation of rat serum ceruloplasmin levels did not render low plus very low density lipoproteins more prone to oxidation in vitro. Thus, high ceruloplasmin levels in vivo are not necessarily associated with high lipoprotein oxidation rates.

Hepatitis C associated glomerulonephritis

To determine the prevalence and type of glomerulonephritis (GN) associated with hepatitis C virus (HCV) cirrhosis, we prospectively evaluated 28 consecutive Saudi patients with HCV cirrhosis for liver transplantation. Six patients (21%) underwent kidney biopsies for proteinuria, unexplained elevated serum creatinine or both. All 6 had GN, 4 had membranoproliferative, one focal segmental and one membranous GN. Immunologic and electron microscopic studies demonstrated immune complex deposition in the glomeruli. Two patients with significant proteinuria were treated with interferon alpha for 3 months with improvement in kidney and liver function. To our knowledge, this is the first report of focal segmental GN associated with HCV. This high prevalence of HCV associated GN is alarming and warrants further studies in cirrhotic and noncirrhotic patients, particularly as an indication for therapeutic intervention.

Mechanism of irrigation effects on gingivitis

Although gingivitis is initiated by plaque and plaque removal controls gingivitis, gingival irrigation with water has been shown to reduce gingivitis without reducing plaque. This study attempted to explore possible mechanisms involved in the treatment of gingivitis by water irrigation. Patients (n = 125) with more than 20 teeth, less than 4 sites with probing depth (PD) deeper than 6 mm, bleeding on probing (BOP) frequency of 30% or higher, and no systemic disease were randomized to one of four treatment groups: toothbrushing alone (brush), toothbrushing plus chlorhexidine 0.12% rinse 2x/day (CHX), toothbrushing plus water irrigation 1x/day (irr+H2O), or toothbrushing plus chlorhexidine 0.04% irrigation 1x/day (irr+CHX). Six sites/tooth were examined at baseline, and at 3 and 6 months for BOP and PD using an automated probe, and for gingival index (GI) and plaque index (PI) by standard means. A prophylaxis and oral hygiene instructions were provided after baseline and 6 month measurements. Subgingival microbial samples and crevicular fluid (GCF) were collected from 2 teeth/subject at each time point. Microbial samples were processed for anaerobic culture and the predominant cultivable flora was determined. CHX and irr+CHX had a 30 to 35% decrease in mean PI, while brush and irr+H2O had only a 12 to 16% decrease. BOP was reduced by 14% in the brush group and 23 to 24% in the other groups. GI was significantly correlated with PI in the brush, CHX, and irr+CHX groups, but not in the irr+H2O group. Prevotella intermedia was significantly reduced in both irrigation groups, but not CHX or brush groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and microbiological effects of controlled-release locally delivered minocycline in periodontitis

The clinical efficacy of minocycline in a subgingival local delivery system was evaluated alone (M) or as an adjunct to scaling and root planing (M + SRP), in comparison to scaling and root planing (SRP) or to no subgingival treatment (NoTx) in adult periodontitis. Fifty-one adult patients with > or = 7 mm periodontal pockets demonstrating the presence by culture of Porphyromonas gingivalis (Pg), Prevotella intermedia (P(i)), or Actinobacillus actinomycetemcomitans (Aa) were randomized into one of the above 4 treatment groups. All sites > or = 5 mm in the most diseased quadrant in each patient received the therapy. Other quadrants were not treated. All patients received standardized oral hygiene instructions at the beginning of the study. At 0, 1, 3 and 6 months following therapy the 7 mm experimental sites were evaluated for selected periodontal pathogens by DNA probe analysis. At these same time points, the plaque index, gingival index, and bleeding on probing were evaluated as well as probing depth and relative clinical attachment level which were assessed by means of an automated probe. Probing depth reduction with M + SRP was significantly greater than all other groups at one month and significantly greater than NoTx and SRP at 3 months. There were no differences in probing depth reduction among groups at 6 months. At 6 months the gain in clinical attachment level was significantly greater for SRP than for either the NoTx or M groups. The prevalence of Pg decreased significantly in the M and M + SRP groups at one month.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of early postoperative surface echocardiography in the pediatric cardiac intensive care unit

OBJECTIVE

To compare surface echocardiographic data with catheterization and surgical observation as a way of deciding on the need to reoperate to correct hemodynamically important sequelae following pediatric cardiac surgery; to determine the false-negative diagnosis rate of surface echocardiography.

DESIGN

Case series.

SETTING

Tertiary-care center, pediatric cardiac intensive care unit.

PATIENTS

All 39 patients who underwent reoperation because of hemodynamically significant anatomic sequelae following primary or elective secondary surgery in 1 calendar year.

INTERVENTIONS

None.

MEASUREMENTS

Two-dimensional and color Doppler ultrasound assessment of anatomy and physiology following cardiac surgery.

RESULTS

In 85 percent, surface echocardiography provided sufficient information for surgeons to reoperate on the same admission. Detection of important residual shunts or arterial stenoses and identification of anatomic causes of pulmonary undercirculation (or overcirculation) in palliated single ventricle are feasible.

CONCLUSION

Early postoperative surface echocardiography is a viable way to decide on the hemodynamic adequacy of cardiac surgery.

Concentration and temperature dependence of diluent dynamics studied by line shape experiments on a phosphate ester in polycarbonate

31P Hahn spin echo line shape and proton line shape experiments are reported on bisphenol A polycarbonate (BPAPC)-tris(2-ethylehexyl)phosphate (TOP) systems to study the concentration and temperature dependence of the local dynamics. In an earlier 31P line shape study a lattice model was presented as a framework to interpret the plasticization and antiplasticization behavior of the diluent based on a fractional population given by the type of nearest neighbor contacts in the mixed polymer-diluent glass. In this study, 31P spin echo line shapes of BPAPC, with 5%, 10% and 15% TOP, which monitor the diluent dynamics, at different temperatures and echo delay times are simulated in terms of fast- and slow-moving components, and the resulting fractional populations are compared with that predicted by the lattice model. Comparisons with the lattice model calculations are also made in the simulation of the 1H line shapes on BPAPC with 5% and 10% TOP, which probes both the polymer and diluent dynamics, and on BPAPC with 5% and 10% perdeuterated trioctylphosphate (DTOP), which detects only the polymer motion. Fairly good line shape simulations and agreement between the lattice model and the fitting results at low diluent concentrations are obtained in all cases. Restricted cone motion best describes the slow-moving component in the 31P line shape fittings. For the fast component, rotational Brownian diffusion with a distribution of correlation times corresponding to a stretched exponential function is used. An activation energy Ea of 56 kJ/mol and an exponent alpha of 0.7 for the fractional exponential correlation function are obtained and used to calculate the mechanical loss peak which was compared with the experimental loss data. The plateau character of the fractional population as a function of temperature can also be interpreted and understood in terms of the lattice model.

Iliac crest bone graft. Osteotome versus saw

The strength of saw-harvested vs. osteotome-harvested Smith-Robinson iliac crest grafts from five fresh frozen cadavers was compared. Matched pairs of grafts were harvested, one with a saw and the other with an osteotome from equivalent locations on the two iliac crests of each pelvis. Grafts were tested to failure in axial compression, and load-displacement curves were recorded for each test. Yield load and displacement, ultimate load, and stiffness were calculated, and statistical analysis was performed with the Student t test and three-way analysis of variance. Evaluation of the 66 pairs of grafts revealed that saw-harvested grafts were consistently stronger than were matched grafts harvested with an osteotome. The middle third of the iliac crest produced significantly stronger grafts, and those harvested from younger donors were significantly stronger than those obtained from older donors. Of even greater clinical relevance, saw-harvested grafts were stiffer than osteotome-harvested grafts. Based on these findings, it is recommended that iliac crest grafts harvested for spine fusion be obtained with an oscillating saw rather than with an osteotome.

Metastatic cystosarcoma phyllodes associated with paraplegia: an uncommon complication of an uncommon tumor

Cystosarcoma phyllodes is a rare form of breast cancer that rarely metastasizes. This case represents the first reported case of a pathological spine fracture and neurologic injury as a result of metastatic cystosarcoma phyllodes. Physicians should be aware of a recently identified histological subtype of cystosarcoma that exhibits an increased incidence of hematogenous metastasis.

Relationship of "bleeding on probing" and "gingival index bleeding" as clinical parameters of gingival inflammation

Bleeding on probing (BOP) and the gingival index have been used to clinically characterize the degree of gingival inflammation. It is, however, unclear to what extent these parameters correlate to each other and to probing pocket depth (PD). The purpose of this clinical study was to evaluate the association between BOP and GI bleeding (scores of 2 and 3), as well as the relationship of these variables to PD, in a group of patients presenting with naturally-occurring gingivitis. Based on screening examinations of 125 subjects with at least 20 teeth, no more than 4 sites with PD over 6 mm, a BOP frequency of 30% or greater, and no systemic condition that would influence the inflammatory response, were selected. 2 weeks after screening they were examined at 6 sites per tooth for plaque index, GI, PD and BOP. A standardized pressure sensitive probe (Florida Probe) with 20 g probing force was used for BOP and PD measurements. In this population, means of 40.9% (S.E. = 1.36) BOP sites and 35.3% (S.E. = 1.81) GI bleeding sites per patient were found. A total of 20,008 sites ranging in PD up to 5.9 mm were evaluated; however, the majority of sites (19,723, 98.6%) presented with < 4 mm PD. When sites were evaluated, BOP demonstrated a positive correlation with PD, whereas GI bleeding correlated with PD. For sites characterized by the absence of BOP as well as the absence of GI bleeding (scores 0 and 1), the highest % of agreement between the 2 indices (77.7%) was found in shallow sites (0.1-2 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

Arthroscopic surgery of the knee on the U.S. Naval Hospital Ships during Operation Desert Shield

Between September 1990 and January 1991, while deployed to the Persian Gulf for Operation Desert Shield, 118 patients underwent arthroscopic surgery of the knee on the U.S. Naval Hospital Ships USNS Mercy and USNS Comfort. There were 113 men and 5 women, with an average age of 28 years (range, 19-59 years). The most common findings at the time of arthroscopy were meniscus tears (53%), anterior cruciate ligament tears (29%), and normal arthroscopic examinations (9%). There were three complications, two hemarthroses and one superficial portal site infection. Seventy patients (59%) were able to be returned to duty at an average of 6 days post-operatively, obviating the need to evacuate these patients out of the Middle East theater to Europe or the United States, thus avoiding additional delay, expense, and loss of the service member to his military unit.

The treatment of lumbar disc herniation: simple fragment excision versus disc space curettage

The purpose of this study was to determine whether there was any difference in the clinical outcome between groups of patients treated with lumbar discectomy and vertebral endplate curettage as compared with disc fragment excision without endplate curettage. Eighty-three patients requiring lumbar disc excision for herniated nucleus pulposus were evaluated retrospectively at minimum 2-year follow-up. Forty-three patients had undergone fragment excision and disc space curettage at one center, whereas 40 patients underwent fragment excision without curettage at two other centers. There was no increased rate of reherniation or reoperation in the excision-only group. Vertebral endplate curettage carries a risk of annular penetration and damage to the great vessels. This study shows that this potentially dangerous step of the operation is unwarranted. In addition, patients who underwent endplate curettage had a higher incidence of low-back pain on follow-up.

Immediate closed reduction of cervical spine dislocations using traction

Cervical facet dislocations may be reduced rapidly and effectively using axial traction with weights applied at over the traditional 45-pound limit. Fifty-three sequential patients with cervical facet dislocations were reviewed. Thirty-nine patients required more than 50 pounds of traction to achieve rapid reduction. Sixty-eight percent of the entire series showed significant improvement in neurologic function. There were no cases of significant loss of function. A cadaver study confirmed that the cranial tongs could support over 100 pounds of traction. Careful application of up to 100 pounds seems to be associated with a low risk of neurologic compromise or tong failure, but results in effective reduction of dislocations.

Long-term results of lumbar spine surgery complicated by unintended incidental durotomy

Unintended incidental durotomy is not an infrequent complication of spinal surgery (incidence, 0.3-13% reported). Although prompt repair is advocated, little has been written regarding any consequences of primarily repaired durotomies on long-term patient outcome. A retrospective review of 450 patients undergoing lumbar spine surgery revealed 17 cases (4%) of incidental durotomy, recognized intraoperatively and repaired primarily. These patients were evaluated at long-term follow-up (mean, 25.1 months); and their results were compared with controls matched for age, diagnosis, procedure, and length of follow-up. No differences of statistical significance could be identified in comparing the outcomes of the two groups. Incidental durotomy, when recognized and repaired intraoperatively, does not increase perioperative morbidity or compromise final result.

Failed arthrodesis of the spine for severe spondylolisthesis. Salvage by interbody arthrodesis

Four patients who had had grade-III or grade-IV symptomatic spondylolisthesis and a failed posterior or posterolateral arthrodesis were treated with transperitoneal anterior lumbosacral interbody arthrodesis and fixation with a fibular graft; the procedure was sometimes followed by posterolateral arthrodesis of the spine. The patients were examined ten to twenty-two years after the salvage operation. At follow-up, all had a solid fusion of the fifth lumbar to the first sacral vertebra. No neurological deficits had worsened and no iatrogenic neurological deficits had developed. The slip angle had improved by an average of 23.2 degrees (range, 12 to 35 degrees).

Medical care and mortality: racial differences in preventable deaths

We analyzed deaths of blacks and whites in Alameda County, California where previous studies have documented consistent racial inequalities in health services. We classified each death during 1978 as due to preventable and manageable conditions or as "non-preventable" according to lists compiled by the Working Group on Preventable and Manageable Diseases chaired by Dr. David Rutstein. The total death rate for blacks 0-65 years of age exceeded that of whites by 58 percent (p less than .01). Rates of death due to preventable and manageable conditions for persons aged 0-65 years were 77 percent higher for blacks than for whites (p less than .01). More than one-third of the excess total death rate of blacks relative to whites could be explained by the excess of potentially preventable deaths. Our findings suggest that inequalities in health services reinforce broader social inequalities and are in part responsible for disparities in health status. Improvements in the health and longevity of blacks and other oppressed groups might be achieved by improved access to existing medical, public health, and other preventive measures.

Patient transfers: medical practice as social triage

We studied 458 consecutive patient transfers from 14 private hospitals to a public hospital emergency room during a six-month period. The transferred patients were predominantly male, young, and uninsured, and included large numbers of minority group members. We established criteria to identify patients at high risk for adverse effects of transfer and reviewed the clinical records of the 103 patients meeting these criteria. We judged that transfer resulted in substandard care for 33 of these patients, either because they were at risk for life-threatening complications in transit or because urgently needed diagnosis or therapy was delayed. In the community studied, transfer is a common and potentially dangerous medical intervention which appears to reinforce racial and class inequalities of access to medical care.

Introducing a general prompting and recording system: its effect on client and staff behavior in an institutional ward

This study describes the evaluation of a "low-key" approach to training staff in procedures designed to increase the degree of independence of mentally handicapped people. Training leaflets describing a method of giving graded prompts to residents were distributed to staff on a hospital ward. Subsequently, checklists were introduced on which staff recorded the amount of assistance they gave residents in a variety of self-help skills. Time-sampling observations provided data on residents' engagement in such skills and their degree of independence. The amount of staff prompting was not affected by the interventions. The introduction of each intervention increased the frequency with which staff allowed residents to do tasks independently, but the effect did not persist. The amount of residents' independent activity increased prior to the introduction of the leaflets, remained stable after their introduction, and increased further when checklists were introduced. These results are discussed in terms of the training materials used and the role of supervisors in staff training.

Hypernatremic dehydration in nursing home patients: an indicator of neglect

In order to determine the antecedents of hypernatremic dehydration the authors reviewed the records of 56 patients with this condition at two public hospitals, one of which includes a large chronic care facility. Twenty-nine patients developed hypernatremic dehydration while at nursing homes. All cases came from proprietary nursing homes, although proprietaries account for only 88 per cent of nursing home beds in the community studied (P less than 0.05). There was a cluster of patients from two nursing homes. Sixteen patients admitted from home all showed evidence of inadequate care prior to admission. Eleven patients became hypernatremic while in acute care hospitals. No patient in the public chronic care facility developed hypernatremic dehydration during the period studied. The average serum sodium concentration of patients transferred from nursing homes was significantly higher than that of patients who developed hypernatremic dehydration at home or in acute care hospitals. It is concluded that hypernatremic dehydration in an institutionalized patient may be an indicator of inadequate care, which should prompt further investigation of the living conditions of the patient.