Patient adherence to an oral rehydration solution intervention to prevent dehydration following ileostomy creation: A qualitative study

BACKGROUND

Patients undergoing surgery for ileostomy creation frequently experience postoperative dehydration and subsequent renal injury. The use of oral rehydration solutions (ORS) has been shown to prevent dehydration, but compliance may be variable.

METHODS

Semi-structured qualitative interviews were conducted with 17 patients who received a postoperative hydration kit and dehydration education to assess barriers and facilitators to compliance with ORS kit instructions.

RESULTS

Qualitative analysis revealed five themes affecting patient adherence to the ORS intervention: (1) patient's perception of the effectiveness of the ORS solution, (2) existing co-morbidities, (3) kit quality and taste of the ORS product, (4) quality of the dehydration education, and (5) social support.

CONCLUSIONS

Given that patient adherence can greatly affect the success of an ORS intervention, the design of future ORS interventions should emphasize the educational component, the "patient friendliness" of the ORS kit, and ways that social supports can be leveraged to increase adherence.

Original Research: What Health Care Staff Who Experienced Assisted Patient Falls Can Teach Us: Implications for Fall and Fall Injury Risk

PURPOSE

This quality improvement project had three aims: to identify common assisted falls scenarios, describe staff members' experiences with and risk perceptions of such falls, and explore factors that influenced their perceptions. The overarching goal was to gain useful insight for the development of assisted fall-related strategies and policies.

METHODS

In the fall of 2020, 16 staff members from 13 health care facilities were purposively recruited and interviewed. Transcript summaries of these interviews, along with secondary narrative data from employee and patient injury databases, were analyzed using thematic content analysis.

RESULTS

According to staff members' accounts, assisted falls most commonly took place in patient rooms or bathrooms when patients were ambulating or transferring. The interviewees described assisting falls by grabbing or holding the patient or by using their own body to brace or steady the patient. Interview and secondary narrative data noted various injuries that occurred during assisted fall events. These injuries most often involved the lower back (among staff) and the legs (among patients). Most interviewees perceived that using proper body mechanics would prevent injury.

CONCLUSIONS

Interviewees' experiences with assisted falls indicate areas of improvement for fall prevention. The perception that using proper body mechanics will protect staff from injury may be a misconception. Although the literature reports mixed findings concerning whether staff should assist patient falls, this project's results led us to conclude that there is no safe way to physically assist a falling patient without risk of staff injury.

“We’re all one bad day away”: Impacts on Food Access in Buffalo, New York during the COVID-19 pandemic

When COVID-19 arrived in Buffalo, New York in March 2020, there was already significant food insecurity in the region. However, barriers to food access were greatly exacerbated by the pandemic. This study assesses the pandemic's impact on food access in Buffalo through 75 surveys and 30 qualitative interviews conducted with users of food pantries. Results show that, while the pandemic did contribute to food insecurity, many food pantry users were already experiencing chronic food access issues. Specifically, issues related to transportation, stigma, and chronic poverty must be addressed for food insecure households to better endure emergency events like pandemics.

A multicenter retrospective cohort study comparing urethral diverticulectomy with and without pubovaginal sling

BACKGROUND

Urethral diverticulum is a rare entity and requires a high suspicion for diagnosis based on symptoms and physical exam with confirmation by imaging. A common presenting symptom is stress urinary incontinence (SUI). The recommended treatment is surgical excision with urethral diverticulectomy. Postoperatively, approximately 37% of patients may have persistent and 16% may have de novo SUI. An autologous fascial pubovaginal sling (PVS) placed at the time of urethral diverticulectomy (UD) has the potential to prevent and treat postoperative SUI. However, little has been published about the safety and efficacy of a concomitant pubovaginal sling.

OBJECTIVE

The objective of this study was to compare the clinical presentation, outcomes, complications, and diverticulum recurrence rates in women who underwent a urethral diverticulectomy with vs without a concurrent pubovaginal sling.

STUDY DESIGN

This multicenter, retrospective cohort study included women who underwent a urethral diverticulectomy between January 1, 2000, and December 31, 2016. Study participants were identified by Current Procedure Terminology codes, and their records were reviewed for demographics, medical or surgical history, symptoms, preoperative testing, concomitant surgeries, and postoperative outcomes. Symptoms, recurrence rates, and complications were compared between women with and without a concomitant pubovaginal sling. The primary outcome was the presence of postoperative stress urinary incontinence symptoms. Based on a stress urinary incontinence rate of 50% with no pubovaginal sling and 10% with a pubovaginal sling, we needed a sample size of 141 participants who underwent diverticulectomy without a pubovaginal sling and 8 participants with a pubovaginal sling to achieve 83% power with P<.05.

RESULTS

We identified 485 diverticulectomy cases from 11 institutions who met the inclusion criteria; of these, 96 (19.7%) cases had a concomitant pubovaginal sling. Women with a pubovaginal sling were older than those without a pubovaginal sling (53 years vs 46 years; P<.001), and a greater number of women with pubovaginal sling had undergone diverticulectomy previously (31% vs 8%; P<.001). Postoperative follow-up period (14.6±26.9 months) was similar between the groups. The pubovaginal sling group had greater preoperative stress urinary incontinence (71% vs 33%; P<.0001), dysuria (47% vs 30%; P=.002), and recurrent urinary tract infection (49% vs 33%; P=.004). The addition of a pubovaginal sling at the time of diverticulectomy significantly improved the odds of stress urinary incontinence resolution after adjusting for prior diverticulectomy, prior incontinence surgery, age, race, and parity (adjusted odds ratio, 2.27; 95% confidence interval, 1.02-5.03; P=.043). It was not significantly protective against de novo stress urinary incontinence (adjusted odds ratio, 0.86; 95% confidence interval, 0.25-2.92; P=.807). Concomitant pubovaginal sling increased the odds of postoperative short-term (<6 weeks) urinary retention (adjusted odds ratio, 2.5; 95% confidence interval, 1.04-6.22; P=.039) and long-term urinary retention (>6 weeks) (adjusted odds ratio, 6.98; 95% confidence interval, 2.20-22.11; P=.001), as well as recurrent urinary tract infections (adjusted odds ratio, 3.27; 95% confidence interval, 1.26-7.76; P=.013). There was no significant risk to develop a de novo overactive bladder (adjusted odds ratio, 1.48; 95% confidence interval, 0.56-3.91; P=.423) or urgency urinary incontinence (adjusted odds ratio, 1.47; 95% confidence interval, 0.71-3.06; P=.30). A concomitant pubovaginal sling was not protective against a recurrent diverticulum (adjusted odds ratio, 1.38; 95% confidence interval, 0.67-2.82; P=.374). Overall, the diverticulum recurrence rate was 10.1% and did not differ between the groups.

CONCLUSION

This large retrospective cohort study demonstrated a greater resolution of stress urinary incontinence with the addition of a pubovaginal sling at the time of a urethral diverticulectomy. There was a considerable risk of postoperative urinary retention and recurrent urinary tract infections in the pubovaginal sling group.

Implementing Geographic Information Systems (GIS) into VHA Home Based Primary Care

The Veteran's Health Administration (VHA) Home Based Primary Care (HBPC) program provides comprehensive in-home primary care services to elderly Veterans with complex chronic medical conditions. Nurses have prominent roles in HBPC including as program leaders, primary care providers and nurses who make home visits. Delivery of primary care services to patients in their homes can be challenging due to travel distances, difficult terrain, traffic, and adverse weather. Mapmaking with geographic information systems (GIS) can support optimization of resource utilization, travel efficiency, program capacity, and management during normal operations, and patient safety during disasters. This paper reports on the feasibility, acceptability and outcomes of an initiative to implement GIS mapmaking in VHA HBPC programs. A mixed method evaluation assessed extent of adoption and identified facilitators and barriers to uptake. Results indicate that GIS mapping in VHA HBPC is feasible and can increase effectiveness and efficiency of VHA HBPC nurses.

Vulvovaginal manifestations in Stevens-Johnson syndrome and toxic epidermal necrolysis: Prevention and treatment

The prevalence of acute vulvovaginal involvement in toxic epidermal necrolysis can be as high as 70%; up to 28% of female patients will also develop chronic vulvovaginal sequelae. There is little consensus regarding prevention and treatment of the gynecologic sequelae of both Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN). We review acute and chronic sequelae, including erosions, scar formation, chronic skin changes, urethral complications, adenosis, malignant transformation, vulvodynia, and dyspareunia. We provide comprehensive recommendations for acute and long-term vulvovaginal care in adult and pediatric SJS/TEN patients. Treatment should include an ultrapotent topical steroid, followed by a nonirritating barrier cream applied to vulvar and perineal lesions. A steroid should be used intravaginally along with vaginal dilation in all adults (but should be avoided in prepubertal adolescents) with vaginal involvement. Menstrual suppression should be considered in all reproductive age patients until vulvovaginal lesions have healed. Last, referrals for pelvic floor physical therapy and to surgical subspecialties should be offered on a case-by-case basis. This guide summarizes the current available literature combined with expert opinion of both dermatologists and gynecologists who treat a high volume of SJS/TEN patients.

Newborn screening for X-linked adrenoleukodystrophy in New York State: diagnostic protocol, surveillance protocol and treatment guidelines

PURPOSE

To describe a diagnostic protocol, surveillance and treatment guidelines, genetic counseling considerations and long-term follow-up data elements developed in preparation for X-linked adrenoleukodystrophy (X-ALD) newborn screening in New York State.

METHODS

A group including the director from each regional NYS inherited metabolic disorder center, personnel from the NYS Newborn Screening Program, and others prepared a follow-up plan for X-ALD NBS. Over the months preceding the start of screening, a series of conference calls took place to develop and refine a complete newborn screening system from initial positive screen results to long-term follow-up.

RESULTS

A diagnostic protocol was developed to determine for each newborn with a positive screen whether the final diagnosis is X-ALD, carrier of X-ALD, Zellweger spectrum disorder, acyl CoA oxidase deficiency or D-bifunctional protein deficiency. For asymptomatic males with X-ALD, surveillance protocols were developed for use at the time of diagnosis, during childhood and during adulthood. Considerations for timing of treatment of adrenal and cerebral disease were developed.

CONCLUSION

Because New York was the first newborn screening laboratory to include X-ALD on its panel, and symptoms may not develop for years, long-term follow-up is needed to evaluate the presented guidelines.

Changes in caregiver perceptions over time in response to providing care for a loved one with a primary malignant brain tumor

PURPOSE/OBJECTIVES

To examine how family members of patients with a primary malignant brain tumor transition into the caregiver role and how their perceptions of this transition change over time.

RESEARCH APPROACH

Descriptive, qualitative.

SETTING

Neurosurgery and neuro-oncology clinics of a regional medical center.

PARTICIPANTS

10 family caregivers of patients with a primary malignant brain tumor.

METHODOLOGIC APPROACH

A series of 11 open-ended questions addressing various aspects of the care situation were administered to each caregiver. The same questions were asked at baseline (within one month of the patient's diagnosis) and four months later. Content analysis was performed to identify themes among interviews.

MAIN RESEARCH VARIABLES

Patient changes, caregiver adjustments, and accessing support.

FINDINGS

Caregivers described difficulties stemming from the patient's tumor-related dysfunction and changes in their familial, occupational, and social roles. Support from family and friends was vital to caregivers' emotional health, but shock and fear were evident in all interviews. Becoming subsumed in the care situation was described as enmeshment. Caregivers reported difficulty in communicating with healthcare providers. When looking at change over time, three major themes emerged: Patient Changes: The New Normal; Caregiver Adjustments; and Accessing Support.

CONCLUSIONS

Caregivers require support in handling neurologic and physical sequelae, transitioning into new roles, and avoiding becoming enmeshed in the care situation.

INTERPRETATION

This study underlines the importance of continuing research in this area to provide the necessary interventions that will assist caregivers and provide support throughout their loved one's disease trajectory.

Patients' psychosocial experiences of attending Specialist Palliative Day Care: a systematic review

Recent reviews conclude that the benefits of attending Specialist Palliative Day Care (SPDC) are likely to be in social, psychological and spiritual domains. However, these areas are not easily identified, leaving researchers and practitioners unclear as to what aspects of these domains patients most need and desire. The objective of this review was to systematically evaluate literature on patient-perceived psychosocial experiences of attendance at SPDC. Twelve studies were included. Evidence showed that patients value a person-centred approach that reduces isolation, increases social support, encourages communication and provides activities. Future research could focus on investigating why patients value the psychosocial experiences reported and how these experiences can be defined in a way that would be meaningful to clinical service commissioners. Once this has been done, clinicians can start to measure more effectively clinical effectiveness and devise justifiable interventions to help this patient group.

Perceptions of economic hardship and emotional health in a pilot sample of family caregivers

Although several studies have quantified costs of cancer care; none to date have examined how cancer costs impact family caregivers' emotional health. This study was designed to evaluate how perceptions of economic hardship influence burden, depressive symptoms, and anxiety in family caregivers of persons with a primary malignant brain tumor. Caregiver (CG)/patient dyads (n = 33) were recruited at the time of diagnosis; data were collected at diagnosis and 4 months, and linear regression determined the impact of economic hardship on caregivers' emotional health. Economic hardship did not predict CG burden-schedule at diagnosis or 4 months. Economic hardship predicted burden-abandonment at diagnosis (P < 0.01), but not 4 months. There was a trend for economic hardship to predict CG depressive symptoms at 4 months (P = 0.09), but not at diagnosis. Economic hardship predicted CG anxiety at 4 months (P = 0.06), but not diagnosis. Results suggest caregivers' economic hardship is an important and dynamic aspect of the emotional health of neuro-oncology family caregivers.

Regulation of immune complexes during infection of mice with lactate dehydrogenase-elevating virus: studies with interferon-gamma gene knockout and tolerant mice

Mice persistently infected with lactate dehydrogenase-elevating virus (LDV) develop circulating IgG-containing hydrophobic immune complexes, with a molecular mass of 150 to 300 kd, which bind to the surfaces of high-capacity enzyme-linked immunosorbent assay (ELISA) plates. LDV infection also stimulates polyclonal B-cell activation and autoimmunity. For this study, interferon-gamma gene knockout (GKO) mice were utilized to study circulating immune complexes and other parameters of LDV infection. The kinetics of LDV viremia, formation of plasma IgG anti-LDV antibodies, and LDV replication in the spleen and liver were essentially normal in GKO mice. Polyclonal activation of B cells, as reflected by increased total plasma IgG concentration during LDV infection, was found to be intact in GKO mice, although at a lower magnitude than in control mice. The plasma concentration of IgG-containing hydrophobic immune complexes was reduced about 75% in LDV-infected GKO mice relative to normal LDV-infected controls. Allogeneic tissue responses were also found to be reduced in LDV-infected GKO mice relative to those in normal LDV-infected controls. These results dissociate specific anti-LDV immunity from formation of hydrophobic immune complexes, show that the IgG anti-LDV response as well as LDV replication in the spleen and liver are insensitive to physiological levels of interferon (IFN)-gamma, and suggest that IgG-containing immune complexes stimulated by LDV infection are a marker for autoimmunity.

Trojan Horse macrophages: studies with the murine lactate dehydrogenase-elevating virus and implications for sexually transmitted virus infection

Previous studies have suggested that monocytes or macrophages may mediate internal virus spread. For the present study, the tissue distribution and infectious potential of dye-labelled and/or lactate dehydrogenase-elevating virus (LDV)-infected murine macrophages were determined. Murine peritoneal macrophages were labelled with the fluorescent carbocyanine tracking dye Dil, injected into mice, and the tissue distribution of Dil-labelled cells was determined by fluorescence analysis of frozen sections. Mice receiving intravenous (i.v.) or intraperitoneal injections of Dil-labelled macrophages displayed rapid and broad tissue distribution of the labelled cells. Intravaginal injection of Dil-labelled macrophages resulted in penetration into the placentas, but not the fetuses, of pregnant mice. When macrophages were LDV-infected and Dil-labelled prior to i.v. injection into pregnant mice, they homed to various tissues including the placenta, but were not found in fetuses. Intravaginal injection of LDV-infected macrophages resulted in systemic LDV infection, even though the free-virus dose was less than the minimum infectious dose by this route. Neither polyclonal nor monoclonal IgG anti-LDV antibodies protected mice from vaginal infection with cell-associated virus, and LDV-immune complexes were themselves infectious by the vaginal route. These results show that exogenous macrophages are widely distributed following parenteral injection, penetrate locally to placentas after intravaginal injection, and are capable of acting vaginally as relatively efficient virus infection-delivery vehicles. Thus, 'Trojan Horse' macrophages are potentially infectious vehicles both for internal virus spread and for animal-to-animal transmission.

Determination of the viremia threshold for dental cross-infection in a mouse model

An animal model of dental virus transmission was developed using the lactate dehydrogenase-elevating virus (LDV) of mice to study cross infection. Mouse-to-mouse cross-infection was carried out by scaling the teeth of LDV-infected donor mice with dental instruments, immediately prior to using the contaminated instruments on the teeth of recipient indicator mice. The level of donor viremia was found to correlate with the rate of virus cross-infection, with a viremia threshold level of 10(7.5) ID50/ml observed for dental cross-infection. The blood volume transferred during dental cross-infection was approximately 10(-4) to 10(-5) ml, demonstrating the inefficiency of virus cross-infection, since deposition of about 1000 virions on dental instruments was associated with the threshold limit. Virus transferred during dental cross-infection rapidly entered the blood circulation, showing that dental cross-infection was not dependent on an oral infection. The results from these model studies predict the general inefficiency of dental instrument virus cross-infection, and a further reduced likelihood of dental cross-infection with appropriately cleaned instruments.

Regulation of transplacental virus infection by developmental and immunological factors: studies with lactate dehydrogenase-elevating virus

Placental and fetal infections with lactate dehydrogenase-elevating virus (LDV) were determined by virus titration, indirect fluorescence antibody (IFA), and in situ hybridization with cDNA probes. Experiments were designed to determine the effects of gestational age, timing of maternal LDV infection, and immunological (antibody and cytokine) factors on mouse placental and fetal LDV infection. Virus infection of the placenta was detected at high levels (almost all placentas infected) within 24 h post-maternal infection (p.m.i.), whereas fetal LDV infection was detected only at a low level by 24 h p.m.i. The percentage of fetuses becoming LDV infected progressively increased between 24 and 72 h p.m.i. When fetal infection was studied at 72 h p.m.i., earlier gestational ages (9-11 days) were associated with fetal resistance to infection, whereas between 12.5 and 15 days of gestation, virus infection was detected in 50-71% of fetuses. Maternal treatment with interferon-gamma (IFN-gamma) or anti-LDV monoclonal antibodies was associated with reduced rates of fetal, but not placental, LDV infection. These results demonstrate that both developmental and immunological factors are important in the regulation of transplacental LDV infection.

Cytokine regulation of lactate dehydrogenase-elevating virus: inhibition of viral replication by interferon-gamma

The mechanisms which regulate the replication of lactate dehydrogenase-elevating virus (LDV), a persistent murine model virus which infects macrophages, are unclear. For this study, the effects of murine recombinant interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) on LDV replication were examined. LDV permissiveness was reduced in macrophages obtained from uninfected mice treated with IFN-gamma prior to cell harvest and in vitro LDV infection. Virus inhibition by IFN-gamma was also observed when neonatal LDV-infected mice were injected with this cytokine prior to macrophage harvest and analysis of LDV replication-positive cells. Persistently LDV-infected mice demonstrated an increase in viremia levels following treatment with TNF-alpha. Neither IFN-gamma nor TNF-alpha had any direct in vitro effect on LDV replication in cultured macrophages, suggesting that the actions of these cytokines required secondary or accessory in vivo events. These results provide evidence for cytokine-mediated regulation of LDV infection and support a role for the immune system in the LDV-host relationship.

Non-micelle forming bile acids increase biliary gentamicin excretion in the rat

To investigate whether non-micelle forming bile acids are able to increase biliary gentamicin excretion, male Sprague-Dawley rats were anesthetized with pentobarbital and fitted with a biliary fistula. After a control period of 30 min, dehydrocholate, taurodehydrocholate, or norursodeoxycholate were administered iv at doses of 2 or 10 mumol.min-1.kg-1. Taurodehydrocholate increased bile flow and biliary gentamicin clearance similarly in a dose-dependent fashion. Its unconjugated analogue, in contrast, increased gentamicin clearance fourfold, while increasing bile flow only 1.6-fold. This suggests that other than purely osmotic phenomena were involved. This effect was even more marked for the short-chain bile acid, norursodeoxycholate. At a dose of 2 mumol.min-1.kg-1 it increased bile flow by 30%, but gentamicin clearance by 210%; a similar discrepancy between choleresis and gentamicin clearance was observed at the higher dose tested. It may be concluded that conjugated triketo bile acids increase biliary gentamicin clearance by osmotic choleresis. Unconjugated triketo bile acids and nor-bile acids, to an even greater extent, increase gentamicin clearance much more markedly than bile flow; other effects, such as the putative cholahepatic shunt pathway, are responsible for this phenomenon. This novel therapeutic principle might be useful in achieving therapeutic biliary antibiotic concentrations or in treating gentamicin intoxication in patients with renal insufficiency.

A bile alcohol sulfate as a major component in the bile of the small skate (Raja erinacea)

The nature of bile alcohols and bile acids in gall-bladder and hepatic bile from perfused livers of the small skate (Raja erinacea) has been investigated. The main bile alcohol sulfate was isolated by thin-layer chromatography and analyzed by fast atom bombardment mass spectrometry and 13C NMR. Following solvolysis and purification on Lipidex-DEAP, the bile alcohol profile was measured by capillary gas-liquid chromatography-electron impact mass spectrometry. Based on these studies and on comparison with authentic scymmnol sulfate and scymnol, the main bile alcohol was identified as 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24 xi,26,27-hexol sulfate. The mean +/- SD concentration in gallbladder bile from five different skates was 24.6 +/- 8.7 mmol/l. Only 0.1 mmol/l of cholic acid and its conjugates was found in a pool of skate bile. The main bile alcohol sulfate in the bile of the small skate seems to be a metabolic end product, present in a concentration comparable to that of bile salts in mammals.

Changes in glomerulotubular dimensions, single nephron glomerular filtration rates and the renin-angiotensin system in hypothyroid rats

Glomerular diameters (GD) and lengths of attached proximal convoluted tubules (TPL) were measured in nephrons dissected from the superficial (S), intermediate and juxtamedullary (JM) cortex (7-15 each) of acid-macerated kidneys of weight-matched (E) euthyroid and (H) hypothyroid (2-6 months after radioiodine treatment or thyroidectomy) male Sherman-Wistar rats. Incoordination of growth in H rats was evident in a more marked retardation in kidney than in total body growth. A similar incoordination of microstructural growth was evident in maintenance or GD within normal limits with respect to body weight while attached TPL fell 23% on the average below control values relative to body weight. These changes affected the total nephron population uniformly. As a result, GD/TPL in all nephrons increased significantly (p less than 0.01), by 27% in S and by 29% in JM nephrons. The glomerulotubular dimensional imbalance was associated with a marked and uniformly distributed reduction in single nephron glomerular filtration rate (ferrocyanide method), by 36% in S and JM nephrons. Plasma renin activity fell within normal limits while plasma renin substrate was decreased to 56% of control values. These findings are construed as evidence that growth retardation in hypothyroid rats affects the parenchyma of the kidney (and perhaps other viscera) more than the vasculature.

Infrared Remote Sounding of the Middle Atmosphere of Venus from the Pioneer Orbiter

Orbiter infrared measurements of the Venus atmosphere in the 60- to 140-kilometer region show very small diurnal temperature differences near the cloud tops, increasing somewhat at higher levels. The seasonal (that is, equator to pole) contrasts are an order of magnitude larger, and the temperatures unexpectedly increase with increasing latitude below 80 kilometers. An isothermal layer at least two scale heights in vertical extent is found near the 100-kilometer altitude, where the temperature is about 175 K. Structure is present in the cloud temperature maps on a range of spatial scales. The most striking is at high latitude, where contrasts of nearly 50 K are observed between a cold circumpolar band and the region near the pole itself.

Glomerulotubular dimensional readjustments during compensatory renal hypertrophy in the hypothyroid rat

Although growth of tubules is arrested and that of glomeruli retarded by hypothyroidism in rats, unilateral nephrectomy has been found to elicit a vigorous compensatory hypertrophy of the hypothyroid kidney. Microdissection and measurement of the dimensions of glomeruli and proximal convoluted tubules taken from the kidney removed first and from the hypertrophic contralateral organ removed two to three weeks later, disclosed a "normalization" of the typical glomerulotubular dimensional imbalance as a result of greater tubular than glomerular growth. A somewhat more striking but qualitatively identical response was observed in 9 euthyroid animals. Glomerular filtration rate and maximal glucose reabsorptive capacity (Tm(G)) increased in both euthyroid and hypothyroid animals in accord with the structural shifts.

Lowering of blood pressure, plasma renin substrate, cholesterol and triglyceride by portacaval anastomosis in rats fed on a 60% sucrose/5% lard diet

1. Portacaval anastomosis was carried out in ten rats fed on a 60% sucrose/5% lard diet, which induced moderate hypertriglyceridaemia, mild hypercholesterolaemia and normotension. 2. Plasma triglyceride was decreased to 45% of concentrations observed in ten pair-weighed control rats. 3. Plasma cholesterol concentrations were reduced to 58%, renin substrate to 70% and aortic blood pressure to 80% of control values by portacaval shunt surgery. 4. Individual blood pressures were directly related to plasma renin substrate concentrations.

Effect of diuresis and nephron dimensional heterogeneity on the distribution of nephron filtration rates

Conflicting data in studies of the effect of natriuresis on intrarenal single nephron glomerular filtration rate (SNGFR) redistribution may arise from the interplay of hitherto largely overlooked factors. In the present work, the effect of diuresis induced by saline, glucose or mannitol, as well as the effect of anatomical nephron heterogeneity, were studied. A highly significant positive correlation was found between the logarithm of the urine flow per gram of kidney weight (log V) and the mean superficial (S) to mean juxtamedullary (JM) SNGFR ratio. The rise in S/JM SNGFR with diuresis was primarily a function of decreased JM SNGFR. Total proximal tubular length (TPL) was used as a measure of nephron size. The distribution of nephron sizes was evaluated as S/JM TPL. The effects of urine flow and anatomical heterogeneity on S/JM SNGFR were spearated by means of multiple regression analysis, which yielded the following equation: S/JM SNGFR = -0.049 + 0.179 log V + 0.818 S/JM TPL. Both slopes were highly significant (P less than 0.001). These findings indicate that S/JM SNGFR increases with urine flow, independently of sodium homeostasis, and that anatomical heterogeneity has a marked effect and must, therefore, be controlled. Conflicting data in the literature are harmonized with the present data when appropriate correction can be made for the dimensional factor. There is no evidence that SNGFR redistributions play a role in sodium homeostasis.