High-Stakes Treatment Negotiations Gone Awry: The Importance of Interactions for Understanding Treatment Advocacy and Patient Resistance

Doctors (and sociologists) have a long history of struggling to understand why patients seek medical help yet resist treatment recommendations. Explanations for resistance have pointed to macrostructural changes, such as the rise of the engaged patient or decline of physician authority. Rather than assuming that concepts such as resistance, authority, or engagement are exogenous phenomena transmitted via conversational conduits, we examine how they are dynamically co-constituted interactionally. Using conversation analysis to analyze a videotaped interaction of an oncology patient resisting the treatment recommendation even though she might die without treatment, we show how sustained resistance manifests in and through her doctor's actions. This paradox, in which the doctor can both recommend life-prolonging care and condition resistance to it, has broad relevance beyond cancer treatment; it also can help us to understand other doctor-patient decisional conflicts, for instance, medication nonadherence, delaying emergent care, and vaccine refusal.

Impact of the COVID-19 Public Health Crisis and a Structured COVID Unit on Physician Behaviors in Code Status Ordering

Purpose: Code status orders are standard practice impacting end-of-life care for individuals. This study reviews the impact of a COVID unit on physician behaviors towards goal-concordant end-of-life care at an urban academic tertiary-care hospital. Methods: We conducted a retrospective cohort study of code status ordering on adult inpatients comparing the pre-pandemic period to patients who tested positive, negative and were not tested during the pandemic from January 1, 2019, to December 31, 2020. Results: We analyzed 59,471 unique patient encounters (n = 35,317 pre-pandemic and n = 24,154 during). 1,631 cases of COVID-19 were seen. The rate of code status orders among all inpatients increased from 22% pre-pandemic to 29% during the pandemic (P < .001). Code status orders increased for both patients who were COVID-negative (32% P < .001) and COVID-positive (65% P < .001). Being in a cohorted COVID unit increased code status ordering by an odds of 4.79 (P < .001). Compared to the pre-pandemic cohort, the COVID-positive cohort is less female (50% to 56% P < .001), more Black (66% to 61% P < .001), more Hispanic (6.5% to 5%) and less white (26% to 30% P < .001). Compared to Black patients, white patients had lower odds (.86) of code status ordering (P < .001). Other race/ethnicity categories were not significant. Conclusions: Code status ordering remains low. Compared to pre-pandemic rates, the frequency of orders placed significantly increased for all patients during the pandemic. The largest increase occurred in patients with COVID-19. This increase likely occurred due to protocols in the COVID unit and disease uncertainty.

Death and the treatment imperative: Decision-making in late-stage cancer

Care at the end-of-life in the United States has expanded in the past decade in large part due to structural changes such as increased access to hospice care, the integration of palliative care, policy mandates, and financial incentives. Despite these shifts, research shows that appropriate end-of-life care continues to be underutilized. This paper uses conversation analytic (CA) and ethnographic methods to examine doctor-patient interactions among a sample of 14 Stage IV cancer patients and the way decisions unfold about next steps in treatment during a moment that larger policy changes began to take place following passage of the Affordable Care Act. This work reveals that, despite structures designed to better facilitate end-of-life care transitions for patients in late life, doctors continue to demonstrate interactional hesitancy in discussing the possibility of a patient's end-of-life in treatment discussions and an orientation to the treatment imperative. Examining doctor-patient interaction as one key trouble source in end-of-life care implementation shows in situ evidence that the treatment imperative supersedes the structural shifts supporting less medical intervention in late life.

What Does Coma Mean? Implications for Shared Decision Making in Acute Brain Injury

BACKGROUND

Insufficient attention has been devoted to shared decision-making (SDM) in the setting of acute brain injury (ABI). Communication occupies a central role that has been highlighted in recent research on SDM with brain injured patients, with respect to "the impact of specific clinician words and expressions". In this investigation, we seek to understand lay public understandings of the term "coma."

METHODS

Qualitative analysis of lay interpretations of the term "cComa" using modified open coding of a free-text response question at the end of a survey exploring public attitudes in the context of hypothetical ABI. Respondents (n = 511) were drawn from a convenience sample using Amazon Mechanical Turk. This analysis focuses on respondents' free-text responses to the question: "When doctors say a patient is in a coma, what does that mean?"

RESULTS

We analyzed 206 unique responses in order to derive emergent lay conceptualizations of coma. The following 4 themes emerged in how respondents understood coma: (1) State descriptive. (2) Marker of injury severity. (3) As in distinction (or lack thereof) from brain death or sleep. (4) Covert consciousness. For each concept, we discuss its salient elements and offer representative quotes.

CONCLUSIONS

This study provides preliminary qualitative evidence of lay public understandings of the neurologic term "coma". These findings can have implications for surrogate/family-clinician communications. While a physician may intend "coma" to convey a technical description, a family member or surrogate may interpret it as a very different activity (e.g., prognostication, emotional signaling), setting the stage for miscommunication.

Matter over mind: How mental health symptom presentations shape diagnostic outcomes

Mental health disorders face less stigma today than in the past, yet they continue to be misdiagnosed and at times improperly treated. One account for this problem is that physicians rely exclusively on a verbal interview of patients for diagnosis. Because this diagnostic method is likely to be shaped by the way patients present their symptoms, it is critical that we examine whether and how patients' communication practices shape diagnostic and treatment outcomes. This study examines a sample of 14 encounters involving mental health-related symptoms from a dataset of adult primary care visits. Using conversation analytic methods, I show that when patients present mental health symptoms by simply describing the symptoms, primary care physicians exhibit a preference for providing a physical health diagnosis. Conversely, when patients provide a concrete link between their symptoms and the way the symptoms are disrupting their everyday lives, primary care physicians typically provide a mental health diagnosis.

Health for all? A qualitative study of NGO support to migrants affected by structural violence in northern France

France hosts approximately 368,000 'persons of concern' (e.g. refugees, stateless, people in refugee-like situations, asylum-seekers). Northern France has become a focal area, due to its proximity to the Dover entry-point to the UK and larger numbers of migrants. This study used a structural violence lens to explore the provision of health services to migrants in Calais and La Linière in northern France, to contribute to discourse on the effects of structural violence on non-state service providers and migrants in precarious conditions and inform service provision policies. Our qualitative study design used semi-structured key-informant interviews, conducted in summer 2017 with 20 non-governmental service-providers, 13 who had worked in Calais and 7 in La Linière migrant camp. We analysed interviews thematically, using inductive coding. Themes from analysis were: (i) power dynamics between NGOs and the state; (ii) resource allocation and barriers to accessing services; and (iii) effects of structural violence on social determinants of health. NGO service provision varied due to tense power dynamics between state and NGOs, shifting state requirements, and expanding roles. Interviewees described ongoing uncertainties, and inherent disempowerment associated with humanitarian aid, as negatively affecting migrant health and wellbeing, increasing illness risks, and providing unequal life chances. Structural realities including violence appeared to negatively affect migrant social determinants of health, reducing healthcare access, social inclusion, and sense of empowerment. The role of NGOs in providing migrant health services in northern France was complex and contested. Structural violence negatively affected migrant wellbeing through restricted services, intentional chaos, and related disempowerment. The violence exerted on migrants appeared to diminish their life chances while being an ineffective deterrent, indicating better approaches are needed.

The duality of option-listing in cancer care

OBJECTIVE

Listing more than one option for treatment, termed "option-listing" (OL) is one way to facilitate shared decision-making. We seek to evaluate how oncologists do option-listing in clinical encounters across disease contexts.

METHOD

We coded and transcribed 90 video-recorded interactions between 5 oncologist participants and a convenience sample of 82 patients at 2 large clinics in the western U.S. We used conversation analytic (CA) methods to examine patterns of behavior when oncologists provided more than one treatment option to patients.

RESULTS

In early-stage disease, OL provides patients with options while at the same time constraining those options through expression of physician bias. This effect disappears when cancer is at an advanced stage. In this context, OL is presented without physician preference and demonstrates recission of medical authority.

CONCLUSION

In early-stage contexts, OL functions as a way for physicians to array available options to patients while also communicating their expertise. In advanced-stage contexts, OL functions as a way to minimize treatment options and highlight dwindling possibilities.

PRACTICE IMPLICATIONS

OL is one way to implement shared decision-making, but it can also be used to facilitate a realization that treatment choices are diminishing and disease is progressing beyond a cure.

Invoking death: How oncologists discuss a deadly outcome

Existing sociological research documents patient and physician reticence to discuss death in the context of a patient's end of life. This study offers a new approach to analyzing how death gets discussed in medical interaction. Using a corpus of 90 video-recorded oncology visits and conversation analytic (CA) methods, this analysis reveals that when existing parameters are expanded to look at mentions of death outside of the end-of-life context, physicians do discuss death with their patients. Specifically, the most frequent way physicians invoke death is in a persuasive context during treatment recommendation discussions. When patients demonstrate active or passive resistance to a recommendation, physicians invoke the possibility of the patient's death to push back against this resistance and lobby for treatment. Occasionally, physicians invoke death in instances where resistance is anticipated but never actualized. Similarly, death invocations function for treatment advocacy. Ultimately, this study concludes that physicians in these data invoke death to leverage their professional authority for particular treatment outcomes.

Treatment Recommendations in Oncology Visits: Implications for Patient Agency and Physician Authority

Although oncology is a major site for clinician‒patient treatment negotiation requiring a careful balance of potentially competing viewpoints, little is known about how clinicians promote their treatment recommendations to patients and what the manner of promotion tells us about the oncologist‒patient relationship. Utilizing an already-established schema of coding treatment recommendations, I draw on 61 treatment recommendations to examine treatment decision-making in oncology. This paper investigates how physicians balance asserting their authority while at the same time attending to patient agency and involvement in decision-making. Taking this one step further, this paper explores how physicians negotiate decision-making with patients given that they occupy a liminal state between obligations to policy imperatives and commitments to their professional knowledge and technical expertise. How do they do this, and what accounts for this? To answer these questions, this paper analyzes the ways in which physicians present treatment recommendations and the treatment contexts in which they are made.

Electro-chromic structure with a high degree of dielectric tunability

In conjunction with their electronically reconfigurable optical properties, inorganic, WO₃/LiNbO₃/NiO Electro-Chromic materials (EC) have recently been shown to exhibit a degree of electric field induced dielectric tunability at radio frequencies, to the level comparable with more mature bulk-tuneable technologies. However, the full extent of their dielectric tunability remains fully unexplored, due to a fundamental lack of understanding of its intricate tuning mechanisms. The unveiling of their tuning principles is paramount towards a comprehension of not only their optical and radio frequency dielectric tunability, but also for the creation of EC structures with substantial permittivity tuning ratios. Here, we report on an inorganic, WO₃ and LiNbO₃ – based EC structure with perturbed constituent layers. We developed and synthesised a new EC structure by inserting the chromic layers in the interior of the device and partitioning the electrolyte layer and assigning it to the device’s peripheries. This new arrangement allows for an increase in the dielectric tunability of over three times compared to previously reported standard EC structures in the frequency range from 1–20 GHz.

Eastern Canadian Colorectal Cancer Consensus Conference 2017

The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference 2017 was held in St. John's, Newfoundland and Labrador, 28-30 September. Experts in radiation oncology, medical oncology, surgical oncology, and cancer genetics who are involved in the management of patients with gastrointestinal malignancies participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses multiple topics in the management of gastric, rectal, and colon cancer, including ■ identification and management of hereditary gastric and colorectal cancer (crc);■ palliative systemic therapy for metastatic gastric cancer;■ optimum duration of preoperative radiation in rectal cancer-that is, short- compared with long-course radiation;■ management options for peritoneal carcinomatosis in crc;■ implications of tumour location for treatment and prognosis in crc; and■ new molecular markers in crc.

High Frequency Dielectric Characteristics of Electrochromic, WO3 and NiO Films with LiNbO3 Electrolyte

A great deal of attention has been recently focused on Electrochromic (EC) materials and EC based devices, promoting mainly applications related to display technology. In this case, EC based displays are usually actuated by the application of low dc bias voltages, changing their appearance from transparent to opaque. A variety of studies related to the optical characteristics of EC materials have been reported, however, no serious studies so far have been reported on the possible high frequency tunability of the dielectric characteristics of these materials, with the exception of the work by Rose, which presented the operation of a microwave shutter based on conductive polymers operating in the X-band. Here we report tuneable high frequency dielectric characteristics of an Electrochromic (EC) cell with a complimentary structure of Conductor/WO₃/LiNbO₃/NiO/Conductor in the frequency range from 1 GHz to 20 GHz. The EC cell was prepared using standard semiconductor processing technology, such as lithography, etch and deposition techniques. Our measured results indicate that tunability of high frequency dielectric characteristics as a function of dc bias voltage is achieved, and that a possibility exists for this tunability to be tailored.

Agenda-setting revisited: When and how do primary-care physicians solicit patients' additional concerns?

OBJECTIVE

Soliciting patients' complete agendas of concerns (aka. 'agenda setting') can improve patients' health outcomes and satisfaction, and physicians' time management. We assess the distribution, content, and effectiveness of physicians' post-chief-complaint, agenda-setting questions.

METHODS

We coded videotapes/transcripts of 407 primary-, acute-care visits between adults and 85 general-practice physicians operating in 46 community-based clinics in two states representing urban and rural care. Measures are the incidence of physicians' questions, their linguistic format, position within visits, likelihood of being responded to, and the nature of such responses.

RESULTS

Physicians' questions designed to solicit concerns additional to chief concerns occurred in only 32% of visits (p<.001). Compared to questions whose communication format explicitly solicited 'questions' (e.g., "Do you have any questions?"), those that were formatted so as to allow for 'concerns' (e.g., "Any other concerns?") were significantly more likely to generate some type of agenda item (Chi(2) (1, N=131)=11.96, p=.001), and to do so more frequently when positioned 'early' vs. 'late' during visits (Chi(2) (1, N=73)=4.99, p=.025).

CONCLUSIONS

Agenda setting is comparatively infrequent. The communication format and position of physicians' questions affects patients' provision of additional concerns/questions.

PRACTICE IMPLICATIONS

Physicians should increase use of optimized forms of agenda setting.

"Tiers of delay": warfarin, hip fractures, and target-driven care

Anticoagulation reversal is a common cause of operative delay. We sought to establish for the first time the impact this has on best practice tariff (BPT) for patients with hip fracture admitted on warfarin. All patients with hip fracture treated operatively over a 32-month period were reviewed. Basic demographics, time to theater, length of stay, and mortality were recorded for all patients. Independent samples t-tests were used to identify statistically significant differences between patients on warfarin and those not taking the drug. A total of 83 patients were admitted anticoagulated with a mean international normalized ratio of 2.65 and a median time to theater of 49.7 hours. Of these patients, 79% breached BPT, incurring significant financial loss. In the control group, 908 patients took a median 24.5 hours, a 28% breach of BPT (P < .01). Length of stay, Nottingham Hip Fracture Score, and predicted 30-day mortality were similar for both the groups. As well as affecting clinical outcome following hip fracture, delay due to anticoagulation causes considerable loss of BPT. Potential loss of revenue due to delays over the study period was £80 000, inspiring the establishment of an "early trigger" anticoagulation protocol. Although it is accepted that there are limitations to this work, it should raise awareness of the real impact of warfarin on patients with hip fracture both in terms of outcome and for the first time, loss of potential revenue.

The Best Practice Tariff helps improve management of neck of femur fractures: a completed audit loop

BACKGROUND

The Best Practice Tariff incentivizes hospitals in the UK to improve the care they deliver, and includes a requirement to deliver multiprofessional care to patients with neck of femur fractures. The Best Practice Tariff for 2010-11 included six targets: (1) surgery within 36 hours, (2) admission under consultant-led joint orthopaedic-geriatric care, (3) admission using a multidisciplinary assessment protocol, (4) review by a geriatrician within 72 hours, (5) geriatrician-directed multi-professional rehabilitation, and (6) assessment for falls and bone protection. The authors chose to audit their Trust's compliance with these targets.

METHODS

A retrospective audit was conducted in 2011 at the authors' university-affiliated tertiary care hospital, which is a regional major trauma centre. Only patients 65 years or older, with fragility-type neck of femur fractures who were treated surgically at the authors' unit and were eligible for geriatric review and multiprofessional rehabilitation, were included. The results of this audit (2010-11 Best Practice Tariff targets) were analysed and a series of procedural and logistical measures were introduced. A re-audit was performed in April 2012 for 2011-12, and the results for the 2 years were compared using appropriate statistics (Chi square tests and analysis of variance). Thirty-day mortality was compared using the summary hospital-level mortality indicator.

RESULTS

A total of 410 patients were eligible for Best Practice Tariff in 2010-11, which increased to 463 in 2011-12. The changes from the first year's audit helped increase the rates for 36-hour surgery from 48.3% to 73.4% and for 72-hour geriatric review from 68.8% to 81.8% (P<0.05). The annual Best Practice Tariff achievement increased from 31.7% to 61.3% (P<0.05). The summary hospital-level mortality indicator declined from 96.5 to 61.3.

CONCLUSIONS

Focusing on poorly satisfied Best Practice Tariff indicators can produce a significant improvement in the per capita Best Practice Tariff achievement. Further studies are needed to assess the health and financial gain in detail.

Optimising the use of electronic health records to estimate the incidence of rheumatoid arthritis in primary care: what information is hidden in free text?

Background

Primary care databases are a major source of data for epidemiological and health services research. However, most studies are based on coded information, ignoring information stored in free text. Using the early presentation of rheumatoid arthritis (RA) as an exemplar, our objective was to estimate the extent of data hidden within free text, using a keyword search.

Methods

We examined the electronic health records (EHRs) of 6,387 patients from the UK, aged 30 years and older, with a first coded diagnosis of RA between 2005 and 2008. We listed indicators for RA which were present in coded format and ran keyword searches for similar information held in free text. The frequency of indicator code groups and keywords from one year before to 14 days after RA diagnosis were compared, and temporal relationships examined.

Results

One or more keyword for RA was found in the free text in 29% of patients prior to the RA diagnostic code. Keywords for inflammatory arthritis diagnoses were present for 14% of patients whereas only 11% had a diagnostic code. Codes for synovitis were found in 3% of patients, but keywords were identified in an additional 17%. In 13% of patients there was evidence of a positive rheumatoid factor test in text only, uncoded. No gender differences were found. Keywords generally occurred close in time to the coded diagnosis of rheumatoid arthritis. They were often found under codes indicating letters and communications.

Conclusions

Potential cases may be missed or wrongly dated when coded data alone are used to identify patients with RA, as diagnostic suspicions are frequently confined to text. The use of EHRs to create disease registers or assess quality of care will be misleading if free text information is not taken into account. Methods to facilitate the automated processing of text need to be developed and implemented.

Clinical and economic impact of contaminated blood cultures within the hospital setting

Blood cultures have an important role in the diagnosis of serious infections, although contamination of blood cultures (i.e. false-positive blood cultures) is a common problem within the hospital setting. The objective of the present investigation was to determine the impact of the false-positive blood culture results on the following outcomes: length of stay, hotel costs, antimicrobial costs, and costs of laboratory and radiological investigation. A retrospective case-control study design was used in which 142 false-positive blood culture cases were matched with suitable controls (patients for whom cultures were reported as true negatives). The matching criteria included age, comorbidity score and month of admission to the hospital. The research covered a 13-month period (July 2007 to July 2008). The findings indicated that differences in means, between cases and controls, for the length of hospital stay and the total costs were 5.4 days [95% CI (confidence interval): 2.8-8.1 days; P<0.001] and £5,001.5 [$7,502.2; 95% CI: £3,283.9 ($4,925.8) to £6,719.1 ($10,078.6); P<0.001], respectively. Consequently, and considering that 254 false-positive blood cultures had occurred in the study site hospital over a one-year period, patients with false-positive blood cultures added 1372 extra hospital days and incurred detrimental additional hospital costs of £1,270,381 ($1,905,572) per year. The findings therefore demonstrate that false-positive blood cultures have a significant impact on increasing hospital length of stay, laboratory and pharmacy costs. These findings highlight the need to intervene to raise the standard of blood-culture-taking technique, thus improving both the quality of patient care and resource use.

Pediatric oral health-related quality of life improvement after treatment of early childhood caries: a prospective multisite study

PURPOSE

This study's purpose was to compare changes in parent-reported pediatric oral health-related quality of life between children with early childhood caries (ECC) and children who were caries-free; the ECC children received surgical dental intervention between baseline and follow-up.

METHODS

A newly developed self-report instrument, the POQL, was administered to 501 parents of 2- to 8-year-old children (caries-free=315; ECC=186) in hospital dental clinics in Columbus, Ohio, and Washington, D.C.

RESULTS

At baseline, ECC children were more likely to have fair or poor oral health and were rated as having more pain and trouble with physical, mental, and social functioning due to their teeth or mouth vs caries-free children (P<.001). At 6 and 12 months following dental treatment for ECC, there were significant improvements in parental ratings of their children's oral health status and a significant reduction in problems reported with physical, mental, and social functioning (all P<.001).

CONCLUSIONS

Compared with caries-free children, early childhood caries children were more likely to have worse questionnaire response scores and to experience greater negative impacts on physical, mental, and social functioning. Dental interventions in ECC children had a significant positive impact on parental ratings of their overall oral health and physical, mental, and social functioning.

Genetic linkage of familial granulomatous inflammatory arthritis, skin rash, and uveitis to chromosome 16

Blau syndrome (MIM 186580), first described in a large, three-generation kindred, is an autosomal, dominantly inherited disease characterized by multiorgan, tissue-specific inflammation. Its clinical phenotype includes granulomatous arthritis, skin rash, and uveitis and probably represents a subtype of a group of clinical entities referred to as "familial granulomatosis." It is the sole human model with recognizably Mendelian inheritance for a variety of multisystem inflammatory diseases affecting a significant percentage of the population. A genomewide search for the Blau susceptibility locus was undertaken after karyotypic analysis revealed no abnormalities. Sixty-two of the 74-member pedigree were genotyped with dinucleotide-repeat markers. Linkage analysis was performed under a dominant model of inheritance with reduced penetrance. The marker D16S298 gave a maximum LOD score of 3.75 at theta = .04, with two-point analysis. LOD scores for flanking markers were consistent and placed the Blau susceptibility locus within the 16p12-q21 interval.

N-acetylgalactosaminyl GD1a is a target molecule for serum antibody in Guillain-Barré syndrome

Serum antibodies against such major glycolipids as GM1, GD1b, and LM1 have been reported in patients in the acute phase of Guillain-Barré syndrome (GBS). Because minor unidentified glycolipids also may be targets of antibodies in GBS sera, we assayed serum antibody against a crude ganglioside fraction using thin-layer chromatogram immunostaining. Antibody activity was detected against a band that migrated just below GD1a in 6 of the 50 patients with GBS tested. Antibody titer, as determined by enzyme-linked immunosorbent assay, decreased during the course of the disease. All 6 patients had suffered gastrointestinal infection before the neurological onset of GBS and showed low amplitudes for the compound muscle action potentials and normal or only slightly decreased nerve conduction velocities. Thin-layer chromatogram immunostaining did not show this antibody activity in any of the 16 normal and 119 disease controls. The unidentified glycolipid was isolated by DEAE-Sephadex A-25 column chromatography, sialidase treatment, and Iatrobeads column chromatography. Fast atom bombardment-mass spectra showed it to be N-acetyl-galactosaminyl GD1a.

Molecular computing for edge-enhanced laser imaging

In order to illustrate the self-assembly capability, we consider a laser imaging experiment on a wet film that is made of bacteriorhodopsin (BR) molecules suspended in a diffusion-limited viscous medium. BR wet film is similar to a wet photograph film but having a finer resolution and adaptive pixel locations due to laser-induced thermal diffusion. The synergism between thermal diffusion of BR molecules (induced externally by a write-laser) and molecular photochromism (generated internally by a read-laser) is exploited naturally for edge-enhanced image applications.

Expanded linkage map of Vibrio cholerae

An expanded linkage map of the Vibrio cholerae classical strain 162 chromosome has been prepared using a variety of new auxotrophic mutants. The chromosome consists of a single, linear linkage group. The map consists of 17 markers, which have been ordered; 20 mutational sites, which are tentatively ordered; five markers (ura-1, ser-2, mal-1, man-1, suc-1), which are linked but unordered; and three mutations (aro-2, cys-2 and cys-6) which showed little or no linkage. A proposal is made to standardize genetic nomenclature in V. cholerae genetic studies.

A study of the transmission and structure of double stranded RNAs associated with the killer phenomenon in Saccharomyces cerevisiae

Killer strains contain two double stranded RNAs, L and M. The M dsRNA appears to be necessary for production of a toxin and for resistance to that toxin. Mutant strains have been found that are defective in their ability to kill and in their resistance to toxin. These sensitive, non-killer strains have altered dsRNA composition. One class has no M dsRNA. Another class of sensitive, non-killers called suppressives has no M dsRNA but instead has smaller dsRNAscalledS. Indiploidsresulting from a cross of a wild-type killer by a suppressive the transmission of the M dsRNA is suppressed by the S dsRNA. When a suppressive is crossed by a strain with no M dsRNA, the diploids and all four meiotic spores have the S dsRNA characteristic of the parental suppressive strain. Suppressive strains do not suppress each other. Intercrosses between two different suppressives yields diploids with both parental S dsRNAs. These two S dsRNAs are transmitted to all 4 meiotic progeny. Another class of mutants has been found which is defective for one of the traits but retains the other. One type, temperature-sensitive killers, has a normal dsRNA composition but is unable to kill at 30 degrees. The other type, immunity-minus, has a complex dsRNA pattern. The immunity-minus strain is extremely unstable during mitotic growth and segregates several different types of non-killers. Analysis of the dsRNAs from wild type and the mutants by electron microscopy shows that the L, M, and S dsRNAs are linear. All strains regardless of killer phenotype appear to have the same size L dsRNA.

Mitochondrial proliferation within the nephron. I. Comparison of mitochondrial hyperplasia of tubular regeneration with compensatory hypertrophy

MITOCHONDRIAL PROLIFERATION IN THE RENAL PROXIMAL TUBULAR EPITHELIUM IN RESPONSE TO TISSUE LOSS HAS BEEN QUANTITATED BY TWO DIVERSE MODELS: acute tubular necrosis induced by mercuric chloride and unilateral nephrectomy. The increased work demand on the remaining tubular mass in both models has probably stimulated both cell hyperplasia and hypertrophy. In both instances, cell hyperplasia preceeds hypertrophy. During the cellular hypertrophy, mitochondria first proliferate in number and then increase in size; presumably to satisfy the greater need for energy metabolism necessary during increased active transtubular solute transport.

Repair of the nephron following injury with mercuric chloride

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Effects of Infrared Irradiation on the Tissues of the Rabbit

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