Association of day-case rates with post COVID-19 recovery of elective laparoscopic cholecystectomy activity across England

INTRODUCTION

The aim of this study was to investigate the safety of day-case laparoscopic cholecystectomy, and the association between day-case rates and, post the COVID-19 pandemic, recovery of activity to prepandemic levels for integrated care boards (ICBs) in England.

METHODS

This was a retrospective observational study of the Hospital Episodes Statistics (HES) data set. Elective laparoscopic cholecystectomies for the period 1 January 2019 to 31 December 2022 were identified. Activity levels for 2022 were compared with those for the whole of 2019 (baseline). Day-case activity was identified where the length of stay recorded in the HES was zero days.

RESULTS

Data were available for 184,252 patients across the 42 ICBs in England, of which 120,408 (65.3%) were day-case procedures. By December 2022, activity levels for the whole of England had returned to 88.2% of prepandemic levels. The South West region stood out as having recovered activity levels to the greatest extent, with activity at 97.3% of prepandemic levels during 2022. The South West also had the highest postpandemic day-case rate at 74.9% of all patients seen as a day-case during 2022; this compares with an England average of 65.3%. At an ICB level, there was a significant correlation between day-case rates and postpandemic activity levels (r = 0.362, p = 0.019). There was no strong or consistent evidence that day-case surgery had poorer patient outcomes than inpatient surgery.

CONCLUSIONS

Recovery of elective laparoscopic cholecystectomy activity has been better in South West England than in other regions. Increasing day-case rates may be important if ICBs in other regions are to increase activity levels up to and beyond prepandemic levels.

Factors associated with conversion from day-case to in-patient elective inguinal hernia repair surgery across England: an observational study using administrative data

PURPOSE

Elective primary inguinal hernia repair surgery is increasingly being conducted as a day-case procedure. However, some patients planned for day-case surgery have to stay in hospital for at least one night. The aim of this study was to identify the factors associated with conversion from day-case to in-patient management for elective inguinal hernia repair surgery.

METHODS

This was an exploratory retrospective analysis of observational data from the Hospital Episode Statistics dataset for England. All patients aged ≥ 17 years undergoing a first elective inguinal hernia repair between 1st April 2014 and 31st March 2022 that was planned as day-case surgery were identified. The exposure of interest was discharged on the day of admission (day-case) or requiring overnight stay. The primary outcome of interest was 30-day emergency readmission with an overnight stay. For reporting, providers were aggregated to an Integrated Care Board (ICB) level.

RESULTS

A total of 351,528 planned day-case elective primary inguinal hernia repairs were identified over the eight-year study period. Of these, 45,305 (12.9%) stayed in hospital for at least one night and were classed as day-case to in-patient stay conversions. Patients who converted to in-patient stay were older, had more comorbidities, and were more likely to have bilateral surgery and be operated on by a low-annual volume surgeon. Post-procedural complications were strongly associated with conversion. Across the 42 ICBs in England, model-adjusted conversion rates varied from 3.3% to 21.3%.

CONCLUSIONS

There was considerable variation in conversion to in-patient stay rates for inguinal hernia repair across ICBs in England. Our findings should help surgical teams to better identify patients suitable for day-case inguinal hernia repair and plan discharge services more effectively. This should help to reduce the variation in conversion rates.

Day-case and in-patient elective inguinal hernia repair surgery across England: an observational study of variation and outcomes

PURPOSE

Elective primary inguinal hernia repair surgery is increasingly being conducted as a day-case procedure. However, in England there is evidence of wide variation in day-case rates across hospitals. Reducing the extent of this variation has the potential to support more efficient use of resources (e.g., clinician time, hospital beds) and help the recovery of elective surgical activity following the COVID-19 pandemic. The aims of this study were to explore the extent of variation in day-case rates across healthcare providers in England and to evaluate the safety of day-case elective primary inguinal hernia repair surgery.

METHODS

This was an exploratory, retrospective analysis of observational data from the Hospital Episode Statistics data set for England. All patients aged ≥ 17 years undergoing a first elective inguinal hernia repair between 1st April 2014 and 31st March 2022 were identified. The exposure of interest was day-case or in-patient stay, and the primary outcome of interest was 30-day emergency readmission with an overnight stay. For reporting, providers were aggregated to an Integrated Care Board (ICB) level.

RESULTS

A total of 413,059 elective primary inguinal hernia repairs were identified over the 8-year study period. Of these, 326,833 (79.1%) were day-case procedures. During the most recent financial year (2021-22), the highest day-case rate for an ICB was 93.8% and the lowest 66.1%. After adjusting for covariates, day-case surgery was associated with significantly lower rates of 30-day emergency readmission (odds ratio (OR) 0.61, 95% confidence interval (CI) 0.58-0.64, p < 0.001) and for the secondary outcomes 180-day mortality and haemorrhage, infection and pain at 30-day post-discharge. Rates of 30-day emergency readmission were significantly lower in ICBs with high rates of day-case surgery (OR 0.84, 95% CI 0.74-0.96, p < 0.001) than in ICBs with low rates of day-case surgery, although rates of post-procedural haemorrhage within 30 days of discharge were significantly higher in trusts with high day-case rates (OR 1.20, 95% CI 1.04-1.40, p = 0.015).

CONCLUSIONS

For the outcomes studied, we found no consistent evidence that day-case elective inguinal hernia repair was unsafe for selected patients. Currently, there is substantial variation between ICBs in terms of delivering day-case surgery. Reducing this variability may help address the current pressures on the NHS in elective surgery.

Coronary artery stenosis and vulnerable plaque quantification on CCTA by deep learning methods

Introduction

Coronary computed tomography angiography (CCTA) has emerged as a reliable non-invasive modality to assess coronary artery stenosis (CAS) severity and vulnerable plaque (VP). However, comprehensive CCTA assessment, especially VP, is time-consuming and dependent on reader expertise, limiting CCTA's true potential.

Purpose

In this study, we aim to develop and validate a deep learning (DL) based system capable of evaluating CAS severity and characterising VP on CCTA.

Methods

A DL system was trained to assess CAS severity on 3909 expert annotated vessels. A subset of 824 vessels was used to train the model to assess for the presence of VP. The model was based on a 2D U-Net and 3D convolutional neural network architecture. The system automatically performed vessel tracking and segmentation to quantify stenosis severity and characterise the presence of VP. CAS severity was categorised as 0%, 1–49% and ≥50%. VP was defined as: low attenuation plaque (LAP; ≤30 Hounsfield units), positive remodelling (PR; ≥10% diameter) and spotty calcification (SC; &lt;3mm). The model was then tested on 1435 vessels for CAS (mean calcium score 197±502) and a subset of 365 vessels for VP (mean calcium score 419±551), and its diagnostic performance compared with expert readers.

Results

The CAS testing data had a prevalence of 75% (1080/1435), 18% (257/1435) and 6.8% (98/1435) for 0%, 1–49% and ≥50% stenosis, respectively. VP was present in 20% (72/365) in the respective dataset with 44% (32/72) LAP, 19% (14/72) PR and 36% (26/72) SC. Average analysis time for CAS severity and VP was 3.7±2.0s and 3.5±1.8s, respectively. Diagnostic performance of our system is summarised in Tables 1 (CAS severity) and 2 (VP characteristics).

Conclusions

We developed an DL based system capable of rapidly evaluating CAS severity and characterising VP on CCTA. Our system demonstrated high specificity and accuracy for both CAS severity and VP quantification when compared with expert readers.

Funding Acknowledgement

Type of funding sources: None.

856 The Croydon Elective Centre - Surgical Hub Supporting Patient Care and Surgical Training

Aim

NHSE/I and the RCS England have advocated that the separation of elective and surgical care is fundamental in recovering surgical services. It is suggested that the separation is physical, and many Trusts are transforming pathways into elective and emergency hospitals. Croydon Hospital (CHS) have created an alternative, with ‘a Hospital within a Hospital’, separating these pathways within one estate, and considers whether this is a successful model for the future.

Method

The day surgery unit on the ground floor was converted into an emergency centre with an ambulatory surgical hub, a hot clinic, clinical space, 4 emergency theatres and an USS room. The main theatre suite was converted into the Croydon Elective Centre (CEC) with a 12-bedded coronary catheter suite, a lift onto the second floor, 10 theatres, a 12 bedded children's day unit, Moorfields’ eye unit, a new canteen, an admissions unit as well as a 28-bedded elective ward with a new 4-bedded level 1.5 critical care unit.

Results

At the end of wave 1, 3,068 patients awaited treatment, an increase of 30.44% of baseline activity with theatre activity at 28% of normal activity. Activity resumed to 100% within 6 weeks of CEC go live. 2/9,606 patients were Covid-19 positive in the first year. During wave 2, 60% of pre-Covid-19 activity continued. Currently, 2,098 patients await treatment.

Conclusion

The implementation of a surgical hub has supported the treatment of patients as well as provided continuous training opportunities for surgical and anaesthetic trainees as well as the theatre team.

Graphene Supported MoS2 Structures with High Defect Density for an Efficient HER Electrocatalysts

The development of novel efficient and robust electrocatalysts with sufficient active sites is one of the key parameters for hydrogen evolution reactions (HER) catalysis, which plays a key role in hydrogen production for clean energy harvesting. Recently, two-dimensional (2D) materials, especially those based upon transition metal dichalcogenides such as molybdenum disulfide (MoS₂), have gained attention for the catalysis of hydrogen production because of their exceptional properties. Innovative strategies have been developed to engineer these material systems for improvements in their catalytic activity. Toward this aim, the facile growth of MoS₂ clusters by sulfurization of molybdenum dioxide (MoO₂) particles supported on reduced graphene oxide (rGO) foams using the chemical vapor deposition (CVD) method is reported. This approach created various morphologies of MoS₂ with large edges and defect densities on the basal plane of rGO supported MoS₂ structures, which are considered as active sites for HER catalysis. In addition, MoS₂ nanostructures on the surface of the porous rGO network show robust physical interactions, such as van der Waals and π-π interactions between MoS₂ and rGO. These features result in an improved process to yield a suitable HER catalyst. In order to gain a better understanding of the improvement of this MoS₂-based HER catalyst, fully atomistic molecular dynamics (MD) simulations of different defect geometries were also performed.

Interface and defect engineering of hybrid nanostructures toward an efficient HER catalyst

The hydrogen evolution reaction (HER) plays a key role in hydrogen production for clean energy harvesting. Designing novel efficient and robust electrocatalysts with sufficient active sites and excellent conductivity is one of the key parameters for hydrogen production using water splitting devices. Recently, low-dimensional carbon materials have gained attention as metal-free catalysts for hydrogen production. Such nanostructures need to be engineered to improve their catalytic activity. Here, we designed and synthesized a B and N doped carbon nanostructure (CNS)-hBN heterostructure as an improved HER catalyst. The hBN layers on CNS could provide exposed defects and edges that act as active sites for proton adsorption and reduction. The composition, structure and chemical properties of the B and N doped CNS-hBN heterostructure were tuned to obtain excellent HER activity. Detailed morphological, structural and electrochemical characterization demonstrated that the synergistic effect rising from the interaction between B and N doped CNS and hBN structures contributes to enhance the electrocatalytic performances. To get more insight into the role of defects and doping, we performed density functional theory (DFT) calculations on the CNS-hBN heterostructure.

Lightweight Hexagonal Boron Nitride Foam for CO2 Absorption

Weak van der Waals forces between inert hexagonal boron nitride (h-BN) nanosheets make it easy for them to slide over each other, resulting in an unstable structure in macroscopic dimensions. Creating interconnections between these inert nanosheets can remarkably enhance their mechanical properties. However, controlled design of such interconnections remains a fundamental problem for many applications of h-BN foams. In this work, a scalable in situ freeze-drying synthesis of low-density, lightweight 3D macroscopic structures made of h-BN nanosheets chemically connected by poly(vinyl alcohol) (PVA) molecules via chemical cross-link is demonstrated. Unlike pristine h-BN foam which disintegrates upon handling after freeze-drying, h-BN/PVA foams exhibit stable mechanical integrity in addition to high porosity and large surface area. Fully atomistic simulations are used to understand the interactions between h-BN nanosheets and PVA molecules. In addition, the h-BN/PVA foam is investigated as a possible CO₂ absorption and as laser irradiation protection material.

Zirconia based dental ceramics: structure, mechanical properties, biocompatibility and applications

Zirconia (ZrO₂) based dental ceramics have been considered to be advantageous materials with adequate mechanical properties for the manufacturing of medical devices.

Enhanced supercapacitor performance of a 3D architecture tailored using atomically thin rGO–MoS2 2D sheets

A stable, conductive, additive-free and scalable 3D architecture supercapacitor electrode fabricated by atomically thin 2D sheets of GO and MoS₂ shows superior electrochemical properties which are further substantiated using MD simulations.

Administration of D-Alanine-[Ang-(1-7)] (A-779) Prior to Pregnancy in Sprague Dawley Rats Produces Antidiuresis in Late Gestation

We previously demonstrated that angiotensin-(1-7) [Ang-(1-7)], which is increased in the kidney and urine during pregnancy, influences normal fluid expansion of pregnancy. These previous studies were completed by chronic administration of the Ang-(1-7) receptor antagonist D-Alanine-[Ang-(1-7)] (A-779) at a dose of 48 μg/kg/hr after the start of pregnancy (gestational days 11-19). To further explore the role of Ang-(1-7) on kidney function during early, middle, and late pregnancy, Sprague Dawley rats were chronically pretreated 8 days prior to pregnancy and throughout pregnancy (gestational days 0-19) with vehicle or A-779 at a dose of 24 μg/kg/hr. Metabolic studies were completed in virgin animals and throughout pregnancy (gestational days 4-5, 14-15, and 18-19). Chow consumption and water intake increased throughout pregnancy while the difference between intake and output (balance) was increased only at late (day 19) pregnancy with both vehicle and A-779 administration. Urine volume and urinary osmolality were significantly increased and decreased respectively throughout pregnancy in vehicle treated rats only. In late (19 day) pregnancy, A-779 administration significantly decreased chow consumption and water intake. In virgin animals, A-779 administration significantly increased urine volume, while during late pregnancy (19 day), urine volume was significantly decreased with A-779 administration. These studies using pretreatment with a lower dose of A-779 prior to pregnancy confirm results of higher dose A-779 administration after the start of pregnancy. These studies show that Ang-(1-7) produces antidiuresis in virgin rats and diuresis in late gestation. Ang-(1-7) also contributes to the enhanced water intake during pregnancy allowing maintenance of the normal volume expanded state despite diuresis.

Angiotensin-(1-7) serves as an aquaretic by increasing water intake and diuresis in association with downregulation of aquaporin-1 during pregnancy in rats

We previously demonstrated that kidney and urine levels of angiotensin-(1-7) [ANG-(1-7)] were increased in pregnancy. To explore the role of ANG-(1-7) on fluid and electrolyte homeostasis during pregnancy, we evaluated the effect of the ANG-(1-7) antagonist d-alanine-[ANG-(1-7)] (A-779) on kidney function. Virgin and pregnant rats received infusion of vehicle or A-779 (48 μg·kg−1·h−1) for 8 days by osmotic minipumps. Metabolic studies were done on treatment day 7–8. Virgin and pregnant rats at day 15 and 19 were killed, and blood and kidneys were collected. Kidneys were prepared for Western blot analysis for aquaporin-1 (AQP1) and aquaporin-2. In virgin female rats, A-779 increased urine volume and decreased urinary osmolality and AQP1 with no change in water intake. In 19-day pregnant rats, A-779 significantly decreased water intake and urine volume and increased urinary osmolality and kidney AQP1 expression. Only in late gestation did A-779 treatment decrease the difference between intake and output (balance). A-779 treatment increased plasma vasopressin in late gestation but did not change vasopressin in virgins. In virgin and pregnant animals, A-779 administration had no effect on blood pressure, plasma volume, blood volume, or urinary electrolytes. These results suggest that ANG-(1-7) produces antidiuresis associated with upregulation of AQP1 in virgin rats, whereas ANG-(1-7) produces diuresis in late gestation with downregulation of AQP1. ANG-(1-7) contributes to the enhanced water intake during pregnancy, allowing maintenance of the normal volume-expanded state despite diuresis produced in part by decreased AVP and AQP1.

Temporal-spatial expression of ANG-(1-7) and angiotensin-converting enzyme 2 in the kidney of normal and hypertensive pregnant rats

We recently demonstrated that renin-angiotensin system (RAS) overactivity during late gestation in rats is associated with increased kidney and urine levels of ANG-(1-7) and enhanced kidney immunostaining of ANG-(1-7) and angiotensin-converting enzyme 2 (ACE2). To understand the temporal-spatial changes in normal and hypertensive pregnancies, the renal distribution of ANG-(1-7) and ACE2 in association with kidney angiotensin peptides and ACE2 activity was examined in virgin, normal pregnant (NP; gestational days 5, 15, and 19) and reduced uterine perfusion pressure (RUPP at day 19) pregnant Sprague-Dawley rats. ANG-(1-7) and ACE2 immunocytochemical staining increased 1.8- and 1.9-fold and 1.7- and 1.8-fold, respectively, at days 15 and 19 of NP, compared with virgin rats. ANG-(1-7) and ANG II concentrations were increased in the kidney at 19 days of gestation. ACE2 activity measured using a fluorescent substrate was increased 1.9- and 1.9-fold in the cortex and 1.9- and 1.8-fold in the medulla at days 15 and 19 of NP. In the RUPP animals, ANG-(1-7) immunostaining and concentration were significantly decreased compared with 19-day NP rats. ACE2 activity was unchanged in the cortex and medulla of RUPP rats. In conclusion, during NP, the concurrent changes of ACE2 and ANG-(1-7) suggest that ACE2 plays an important role in regulating the renal levels of ANG-(1-7) at mid to late gestation. However, the decrease in renal ANG-(1-7) content in the absence of a concomitant decrease in ACE2 implicates the participation of other ANG-(1-7) forming or degrading enzymes during hypertensive pregnancy.

Enhanced expression of Ang-(1-7) during pregnancy

Pregnancy is a physiological condition characterized by a progressive increase of the different components of the renin-angiotensin system (RAS). The physiological consequences of the stimulated RAS in normal pregnancy are incompletely understood, and even less understood is the question of how this system may be altered and contribute to the hypertensive disorders of pregnancy. Findings from our group have provided novel insights into how the RAS may contribute to the physiological condition of pregnancy by showing that pregnancy increases the expression of both the vasodilator heptapeptide of the RAS, angiotensin-(1-7) [Ang-(1-7)], and of a newly cloned angiotensin converting enzyme (ACE) homolog, ACE2, that shows high catalytic efficiency for Ang II metabolism to Ang-(1-7). The discovery of ACE2 adds a new dimension to the complexity of the RAS by providing a new arm that may counter-regulate the activity of the vasoconstrictor component, while amplifying the vasodilator component. The studies reviewed in this article demonstrate that Ang-(1-7) increases in plasma and urine of normal pregnant women. In preeclamptic subjects we showed that plasma Ang-(1-7) was suppressed as compared to the levels found in normal pregnancy. In addition, kidney and urinary levels of Ang-(1-7) were increased in pregnant rats coinciding with the enhanced detection and expression of ACE2. These findings support the concept that in normal pregnancy enhanced ACE2 may counteract the elevation in tissue and circulating Ang II by increasing the rate of conversion to Ang-(1-7). These findings provide a basis for the physiological role of Ang-(1-7) and ACE2 during pregnancy.

Intrinsic regional differences in androgen receptors and dihydrotestosterone metabolism in human preadipocytes

Androgens play an important role in regulating the central obesity that is a strong risk factor for cardiovascular disease and insulin resistance. This study confirms that androgen receptors are present in subcultured human preadipocytes, with androgen receptor gene expression and saturable specific dihydrotestosterone binding, dissociation constant 1.02 - 2.56 nM and maximal binding capacity 30.8 - 55.7 fmol/mg protein. There was an intrinsic regional difference in androgen receptor complement, with more androgen receptors in visceral than in subcutaneous preadipocytes. Dihydrotestosterone was metabolised by human preadipocytes, with more androstanediol produced by subcutaneous than visceral preadipocytes. While dihydrotestosterone metabolism was insufficient to explain the regional variation in androgen binding, both of these differences would reduce the androgen responsiveness of the subcutaneous preadipocytes compared with visceral preadipocytes. There were no gender differences in androgen binding or metabolism. While the direct effects of androgens on human PAs remain uncertain, these regional differences suggest that AR-mediated regulation of certain PA functions influences adipose tissue distribution.

Fasting decreases apolipoprotein B mRNA editing and the secretion of small molecular weight apoB by rat hepatocytes: evidence that the total amount of apoB secreted is regulated post-transcriptionally

Two different molecular weight forms of apoB are produced from a common initial transcript via editing of a Gln codon (CAA) to a stop codon (UAA), leading to a truncated translation product (apo BS) that consists of the amino terminal half of the larger form (apoBL). Previous studies have shown that fasting coordinately decreases lipogenesis and the secretion of very low density lipoprotein (VLDL) lipids and apoBS. Secretion of the apoBL is unaffected by fasting. We studied whether editing of apoB RNA is repressed by fasting, thus accounting for the selective decreased secretion of apoBS. Column chromatography of [35S]methionine-labeled lipoproteins secreted by hepatocytes from fed rats showed that essentially all of apoBL is secreted in the VLDL fraction, whereas a significant amount (15%) of apoBS is secreted associated as lipoproteins eluting in the HDL fractions. Fasting decreased the relative amount of apoBS that eluted in the VLDL fractions and increased the amount secreted in the HDL fractions. Consistent with previous results, hepatocytes from fasted rats show a selective twofold decrease in apoBS secretion. Fasting did not affect the relative abundance of apoB RNA, determined by slot blot hybridization assays using two different 32P-labeled cDNA probes coding either for both molecular weight forms or for only the large molecular weight form. However, quantitative of the editing of apoB RNA showed that fasting caused a 60% decrease in the amount of apoB RNA possessing the stop codon. These data show that the editing of apoB RNA is sensitive to metabolic state (i.e., fasting) resulting in a selective decrease in the secretion of apoBS. However, since the total secretion of apoB was decreased by fasting, while apoB mRNA levels remained constant, additional (post-transcriptional) mechanisms play a role in regulating apoB secretion.

Mouse sperm can horizontally transmit type C viruses

Washed, non-viable sperm from AKR and NZB mice contain infectious murine type C viruses (MuLV), whereas similarly treated sperm from Balb/c and probably C57Bl/6 mice do not. Interaction of washed, viable AKR, Balb/c and NZB sperm with tissue culture cells leads to a transfer of infectious MuLV to these cells. The most likely mechanism is infection by virus closely associated with the sperm. Another possible mechanism is the introduction of proviral DNA. These experiments indicate that type C viruses can be found with mouse sperm. They suggest sperm could horizontally transmit these MuLV to animals during copulation and to the germ line of mice during penetration of ova.

Influence of fibrinogen levels in dogs on mortality from hemorrhagic and traumatic shock

1) Fibrinogen levels appear related to the outcome of hemorrhagic shock in dogs. 2) Fibrinogen levels can vary with different animals based on location, disease, stress, nutrition, or other factors. 3) Any experiments in hemorrhagic shock (or anything else) should utilize simultaneous and paired controls of animals from the same source or they may be subject to major error.

Genetics of xenotropic virus expression in mice. I. Evidence for a single locus regulating spontaneous production of infectious virus in crosses involving NZB/B1NJ and 129/J strains of mice

The extent of infectious xenotropic virus expression in homogenized splenic tissues from the high-virus-expressing NZB/BINJ mice and the non-virus-expressing 129/J mice and their crosses has been examined. The data suggest that a single autosomal "dominant-like" gene controls the spontaneous production and release of infectious xenotropic virus in NZB mice. Analysis of infectious virus production in second-backcross families [(F1 X 129) X 129] confirmed this conclusion. Variations in the amount of X-tropic virus released were evident in all genetic crosses. Virus titers (expressed as focus-forming units per milliliter) of supernatant fluid ranged from high levels in the NZB mice to somewhat lower levels in crosses involving the 129 mice. In the absence of a definite pattern in the titers observed in the genetic crosses studied, the term dominant-like is proposed for the single gene regulating the expression of X-tropic virus in NZB mice.

The danger of hemolysis in shock

Intravascular hemolysis is sometimes harmful and often fatal. Other times it is harmless. Dogs were paired and subjected to hemorrhagic shock. One of the pair was given 2 ml/kg of autologous hemolyzed blood before bleeding. The other of the pair was given 2 ml/kg of heparinized autologous blood. All of the animals given heparinized blood survived, whereas, all of the animals given hemolyzed blood died. The animals given hemolyzed blood developed coagulation changes indicative of Disseminated Intravascular Coagulation (DIC), whereas, the dogs given nonhemolyzed blood did not. It is concluded that hemolysis in the presence of shock (slow capillary flow) causes DIC and death. Hemorrhagic shock alone or hemolysis alone was harmless.

Chylous ascites: the first reported surgical cure by direct ligation

A patient with apparently intractable chylous ascites was finally explored after the administration of preoperative lipophilic dye. This made identification of a leaking lacteal possible and ligation resulted in a cure.

Levels of C-type viral p30 antigens in lymphoma-resistant mice

Until relatively recently, interest has largely centered upon the causal role of oncogenic viruses especially with respect to the development of murine lymphomas. Host factors have recently come to the fore and are considered to be effective here, where we note that, in spite of relatively high levels of C-type viral antigen in the AKR X CBA F1 mouse, this hybrid remains relatively lymphoma resistant. Evidence points to an overriding host factor in this situation that is dominant with respect to tumor resistance and furthermore independent of the viral load at least as judged by levels of p30 viral antigen, an assumption confirmed by xc plaque assay.