Modulation of TCR signalling components occurs prior to positive selection and lineage commitment in iNKT cells

iNKT cells play a critical role in controlling the strength and character of adaptive and innate immune responses. Their unique functional characteristics are induced by a transcriptional program initiated by positive selection mediated by CD1d expressed by CD4⁺CD8⁺ (double positive, DP) thymocytes. Here, using a novel Vα14 TCR transgenic strain bearing greatly expanded numbers of CD24^hiCD44^loNKT cells, we examined transcriptional events in four immature thymic iNKT cell subsets. A transcriptional regulatory network approach identified transcriptional changes in proximal components of the TCR signalling cascade in DP NKT cells. Subsequently, positive and negative selection, and lineage commitment, occurred at the transition from DP NKT to CD4 NKT. Thus, this study introduces previously unrecognised steps in early NKT cell development, and separates the events associated with modulation of the T cell signalling cascade prior to changes associated with positive selection and lineage commitment.

It's Not Over Till It's Over: A Prospective Cohort Study and Analysis of "Anesthesia Stat!" Emergency Calls in the Pediatric Post-Anesthesia Care Unit (PACU)

Background

Emergency "Anesthesia Stat!" (AS!) calls remain a common practice in medical centers even when advanced communication infrastructures are available. We hypothesize that the analysis of post-procedure "AS!" calls will lead to actionable insights which may enhance patient safety.

Methods

After institutional review board approval, we prospectively collected data from April 2015 through May 2018 on "AS!" calls throughout the pediatric operating rooms (OR), off-site locations, and post-anesthesia care unit (PACU) at a tertiary university medical center. Data recorded included demographic information, location, time of the event, event duration, vital signs, medications, anesthesia staff, attending anesthesiologist, and staff responding to the call. A narrative account of the event was also documented.

Results

A total of 82 "AS!" calls occurred, with ages ranging from 11 days old to 17 years old. Forty-nine of the 82 calls (60%) occurred at emergence. Seventy-one of the 82 calls (87%) were solely respiratory-related. Thirty-five of 49 emergence calls (71%) occurred in the PACU. Further, 34 of 35 PACU calls (97%) were respiratory-related, with 30 of 35 PACU calls (86%) associated with desaturation requiring intervention by anesthesia staff. Finally, 31 of 35 PACU calls (89%) occurred within 30 minutes of patient arrival to PACU.

Conclusion

Analysis of "AS!" events from our PACU continues to support the need for the prompt and continuous availability of at least one staff member with advanced airway management skills. Further, pediatric patients undergoing general anesthesia and surgery should likely be monitored for a minimum of 30 minutes following arrival in the PACU.

Multiple sclerosis risk variants regulate gene expression in innate and adaptive immune cells

At least 200 single-nucleotide polymorphisms (SNPs) are associated with multiple sclerosis (MS) risk. A key function that could mediate SNP-encoded MS risk is their regulatory effects on gene expression. We performed microarrays using RNA extracted from purified immune cell types from 73 untreated MS cases and 97 healthy controls and then performed Cis expression quantitative trait loci mapping studies using additive linear models. We describe MS risk expression quantitative trait loci associations for 129 distinct genes. By extending these models to include an interaction term between genotype and phenotype, we identify MS risk SNPs with opposing effects on gene expression in cases compared with controls, namely, rs2256814 MYT1 in CD4 cells (q = 0.05) and rs12087340 RF00136 in monocyte cells (q = 0.04). The rs703842 SNP was also associated with a differential effect size on the expression of the METTL21B gene in CD8 cells of MS cases relative to controls (q = 0.03). Our study provides a detailed map of MS risk loci that function by regulating gene expression in cell types relevant to MS.

Fish associated with a subsea pipeline and adjacent seafloor of the North West Shelf of Western Australia

Information on the potential ecological value of offshore oil and gas infrastructure is required as it reaches the end of its operational life and decisions must be made regarding the best practice option for decommissioning. This study uses baited remote underwater stereo-video systems to assess fish assemblages along an offshore subsea pipeline and in adjacent natural seabed habitats at ∼140 m depth on the North West Shelf of Western Australia. A total of 955 fish from 40 species and 25 families were recorded. Species richness was, on average 25% higher on the pipeline (6.48 ± 0.37 SE) than off (4.81 ± 0.28 SE) while relative abundance of fish was nearly double on the pipeline (20.38 ± 2.81 SE) than in adjacent natural habitats (10.97 ± 1.02 SE). The pipeline was characterised by large, commercially important species known to associate with complex epibenthic habitat and, as such, possessed a biomass of commercial fish ca 7.5 × higher and catch value ca. 8.6 × ($65.11 ± $11.14 SE) than in adjacent natural habitats ($7.57 ± $2.41 SE). This study has added to the knowledge of fish assemblage associations with subsea infrastructure and provides a greater understanding of the ecological and fisheries implications of decommissioning, helping to better inform decision-making on the fate of infrastructure.

Fish associated with a subsea pipeline and adjacent seafloor of the North West Shelf of Western Australia

Information on the potential ecological value of offshore oil and gas infrastructure is required as it reaches the end of its operational life and decisions must be made regarding the best practice option for decommissioning. This study uses baited remote underwater stereo-video systems to assess fish assemblages along an offshore subsea pipeline and in adjacent natural seabed habitats at ∼140 m depth on the North West Shelf of Western Australia. A total of 955 fish from 40 species and 25 families were recorded. Species richness was, on average 25% higher on the pipeline (6.48 ± 0.37 SE) than off (4.81 ± 0.28 SE) while relative abundance of fish was nearly double on the pipeline (20.38 ± 2.81 SE) than in adjacent natural habitats (10.97 ± 1.02 SE). The pipeline was characterised by large, commercially important species known to associate with complex epibenthic habitat and, as such, possessed a biomass of commercial fish ca 7.5 × higher and catch value ca. 8.6 × ($65.11 ± $11.14 SE) than in adjacent natural habitats ($7.57 ± $2.41 SE). This study has added to the knowledge of fish assemblage associations with subsea infrastructure and provides a greater understanding of the ecological and fisheries implications of decommissioning, helping to better inform decision-making on the fate of infrastructure.

Bifurcations and degenerate periodic points in a three dimensional chaotic fluid flow

Analysis of the periodic points of a conservative periodic dynamical system uncovers the basic kinematic structure of the transport dynamics and identifies regions of local stability or chaos. While elliptic and hyperbolic points typically govern such behaviour in 3D systems, degenerate (parabolic) points also play an important role. These points represent a bifurcation in local stability and Lagrangian topology. In this study, we consider the ramifications of the two types of degenerate periodic points that occur in a model 3D fluid flow. (1) Period-tripling bifurcations occur when the local rotation angle associated with elliptic points is reversed, creating a reversal in the orientation of associated Lagrangian structures. Even though a single unstable point is created, the bifurcation in local stability has a large influence on local transport and the global arrangement of manifolds as the unstable degenerate point has three stable and three unstable directions, similar to hyperbolic points, and occurs at the intersection of three hyperbolic periodic lines. The presence of period-tripling bifurcation points indicates regions of both chaos and confinement, with the extent of each depending on the nature of the associated manifold intersections. (2) The second type of bifurcation occurs when periodic lines become tangent to local or global invariant surfaces. This bifurcation creates both saddle-centre bifurcations which can create both chaotic and stable regions, and period-doubling bifurcations which are a common route to chaos in 2D systems. We provide conditions for the occurrence of these tangent bifurcations in 3D conservative systems, as well as constraints on the possible types of tangent bifurcation that can occur based on topological considerations.

Mixing of discontinuously deforming media

Mixing of materials is fundamental to many natural phenomena and engineering applications. The presence of discontinuous deformations-such as shear banding or wall slip-creates new mechanisms for mixing and transport beyond those predicted by classical dynamical systems theory. Here, we show how a novel mixing mechanism combining stretching with cutting and shuffling yields exponential mixing rates, quantified by a positive Lyapunov exponent, an impossibility for systems with cutting and shuffling alone or bounded systems with stretching alone, and demonstrate it in a fluid flow. While dynamical systems theory provides a framework for understanding mixing in smoothly deforming media, a theory of discontinuous mixing is yet to be fully developed. New methods are needed to systematize, explain, and extrapolate measurements on systems with discontinuous deformations. Here, we investigate "webs" of Lagrangian discontinuities and show that they provide a template for the overall transport dynamics. Considering slip deformations as the asymptotic limit of increasingly localised smooth shear, we also demonstrate exactly how some of the new structures introduced by discontinuous deformations are analogous to structures in smoothly deforming systems.

Effect of corticosteroid withdrawal on tacrolimus and mycophenolate mofetil exposure in a randomized multicenter study

As corticosteroid-sparing protocols are increasingly utilized in kidney transplant recipients, it is crucial to understand potential drug interactions between tacrolimus (TAC) and the effect of corticosteroid withdrawal as well as to characterize dose adjustments of mycophenolate mofetil (MMF) in this setting. This prospective, multicenter, randomized, double-blind study included 397 patients who were randomized on posttransplant day 8 to receive either placebo (CSWD) or corticosteroid continuance (CCS). TAC trough levels at week two posttransplant were significantly greater in the CSWD group whereas TAC doses were comparable to the CCS group. This interaction was not observed in the African American subgroup. Higher serum creatinine and potassium levels were also observed in the CSWD group. MMF dose was significantly reduced in the CSWD group by the investigators because of decreased WBC counts, mostly outside of study protocol criteria, despite similar incidence of neutropenia and reported cytomegalovirus infection. Understanding TAC and MMF exposure in the context of corticosteroid-sparing protocols should allow for improved dosing of immunosuppressants and better management of posttransplant patients.

Low penetrance breast cancer susceptibility loci are associated with specific breast tumor subtypes: findings from the Breast Cancer Association Consortium

Breast cancers demonstrate substantial biological, clinical and etiological heterogeneity. We investigated breast cancer risk associations of eight susceptibility loci identified in GWAS and two putative susceptibility loci in candidate genes in relation to specific breast tumor subtypes. Subtypes were defined by five markers (ER, PR, HER2, CK5/6, EGFR) and other pathological and clinical features. Analyses included up to 30 040 invasive breast cancer cases and 53 692 controls from 31 studies within the Breast Cancer Association Consortium. We confirmed previous reports of stronger associations with ER+ than ER- tumors for six of the eight loci identified in GWAS: rs2981582 (10q26) (P-heterogeneity = 6.1 × 10(-18)), rs3803662 (16q12) (P = 3.7 × 10(-5)), rs13281615 (8q24) (P = 0.002), rs13387042 (2q35) (P = 0.006), rs4973768 (3p24) (P = 0.003) and rs6504950 (17q23) (P = 0.002). The two candidate loci, CASP8 (rs1045485, rs17468277) and TGFB1 (rs1982073), were most strongly related with the risk of PR negative tumors (P = 5.1 × 10(-6) and P = 4.1 × 10(-4), respectively), as previously suggested. Four of the eight loci identified in GWAS were associated with triple negative tumors (P ≤ 0.016): rs3803662 (16q12), rs889312 (5q11), rs3817198 (11p15) and rs13387042 (2q35); however, only two of them (16q12 and 2q35) were associated with tumors with the core basal phenotype (P ≤ 0.002). These analyses are consistent with different biological origins of breast cancers, and indicate that tumor stratification might help in the identification and characterization of novel risk factors for breast cancer subtypes. This may eventually result in further improvements in prevention, early detection and treatment.

Associations of breast cancer risk factors with tumor subtypes: a pooled analysis from the Breast Cancer Association Consortium studies

BACKGROUND

Previous studies have suggested that breast cancer risk factors are associated with estrogen receptor (ER) and progesterone receptor (PR) expression status of the tumors.

METHODS

We pooled tumor marker and epidemiological risk factor data from 35,568 invasive breast cancer case patients from 34 studies participating in the Breast Cancer Association Consortium. Logistic regression models were used in case-case analyses to estimate associations between epidemiological risk factors and tumor subtypes, and case-control analyses to estimate associations between epidemiological risk factors and the risk of developing specific tumor subtypes in 12 population-based studies. All statistical tests were two-sided.

RESULTS

In case-case analyses, of the epidemiological risk factors examined, early age at menarche (≤12 years) was less frequent in case patients with PR(-) than PR(+) tumors (P = .001). Nulliparity (P = 3 × 10(-6)) and increasing age at first birth (P = 2 × 10(-9)) were less frequent in ER(-) than in ER(+) tumors. Obesity (body mass index [BMI] ≥ 30 kg/m(2)) in younger women (≤50 years) was more frequent in ER(-)/PR(-) than in ER(+)/PR(+) tumors (P = 1 × 10(-7)), whereas obesity in older women (>50 years) was less frequent in PR(-) than in PR(+) tumors (P = 6 × 10(-4)). The triple-negative (ER(-)/PR(-)/HER2(-)) or core basal phenotype (CBP; triple-negative and cytokeratins [CK]5/6(+) and/or epidermal growth factor receptor [EGFR](+)) accounted for much of the heterogeneity in parity-related variables and BMI in younger women. Case-control analyses showed that nulliparity, increasing age at first birth, and obesity in younger women showed the expected associations with the risk of ER(+) or PR(+) tumors but not triple-negative (nulliparity vs parity, odds ratio [OR] = 0.94, 95% confidence interval [CI] = 0.75 to 1.19, P = .61; 5-year increase in age at first full-term birth, OR = 0.95, 95% CI = 0.86 to 1.05, P = .34; obesity in younger women, OR = 1.36, 95% CI = 0.95 to 1.94, P = .09) or CBP tumors.

CONCLUSIONS

This study shows that reproductive factors and BMI are most clearly associated with hormone receptor-positive tumors and suggest that triple-negative or CBP tumors may have distinct etiology.

Effects of manipulated diet on size and performance of brachyuran crab claws

Crabs grown experimentally on fully shelled prey developed larger and stronger claws than those raised on nutritionally equivalent unshelled prey. When one claw was immobilized, claws also became asymmetrical. These use-induced changes differ from skeletal remodelling in vertebrates and many invertebrates because changes in the rigid exoskeleton can occur only after molting, and claw muscle mass must be reduced substantially before the molt. Such short-term adaptive responses to environmental stimuli, if heritable, could yield long-term evolutionary changes in claw size and, if combined with behavioral biases toward one side (handedness), could also promote the evolution of claw dimorphism.

Synthesis and processing of maize storage proteins in Xenopus laevis oocytes

Xenopus oocytes injected with zein mRNAs efficiently synthesized maize storage proteins for prolonged periods. Under optimal conditions, zein was synthesized at 3 ng/hr and represented approximately 10% of the total protein synthesized in the oocyte. The mRNA from the normal maize inbred line directed synthesis of all the major zein components; however, products of mRNA from the opaque-2 mutant did not contain the largest zein component. Zein proteins synthesized in the oocyte were 2000 daltons smaller than proteins synthesized by cell-free translation of mRNAs in the wheat germ and reticulocyte systems. This result, which suggested that the oocyte processed prezein polypeptides into native zein proteins, was confirmed by amino-terminal sequence analysis of zein proteins from the oocytes. Cyanogen bromide cleavage of translation products from oocytes and the wheat germ system confirmed the existence of several proteins within each of the major zein components. However, we were unable to detect the presence of signal sequences on zein peptides by this technique.

Does contingent reinforcement strengthen operant behavior?

In Experiment 1, pigeons were trained to peck keys with equal food-reinforcement schedules in components that ended with either noncontingent or contingent transitions to a third component with a five-fold richer schedule. Response rates were higher in the initial component with contingent transitions, but resistance to prefeeding or extinction was not consistently greater. Experiment 2 also included noncontingent or contingent transitions to a signaled period of nonreinforcement. There was no effect of the contingency on transitions to nonreinforcement, but the difference in response rates maintained by contingent versus noncontingent transitions to the richer schedule was replicated. In addition, response rates were higher in components that preceded nonreinforcement than in components that preceded the richer schedule. However, resistance to extinction was greater for noncontingent transitions to the richer schedule than to nonreinforcement, implicating stimulus-reinforcer relations in the determination of resistance to change. Resistance to change was also somewhat greater for noncontingent than for contingent transitions to the richer schedule. The latter result, together with the results of Experiment 1 and related research, suggests that response-contingent reinforcement does not increase resistance to change.

Multiple scales of genetic connectivity in a brooding coral on isolated reefs following catastrophic bleaching

Understanding the pattern of connectivity among populations is crucial for the development of realistic and spatially explicit population models in marine systems. Here we analysed variation at eight microsatellite loci to assess the genetic structure and to infer patterns of larval dispersal for a brooding coral, Seriatopora hystrix, at an isolated system of reefs in northern Western Australia. Spatial autocorrelation analyses show that populations are locally subdivided, and that the majority of larvae recruit to within 100 m of their natal colony. Further, a combination of F- and R- statistics showed significant differentiation at larger spatial scales (2-60 km) between sites, and this pattern was clearly not associated with distance. However, Bayesian analysis demonstrated that recruitment has been supplemented by less frequent but recent input of larvae from outside the local area; 2-6% of colonies were excluded from the site at which they were sampled. Individual assignments of these migrants to the most likely populations suggest that the majority of migrants were produced at the only site that was not decimated by a recent and catastrophic coral bleaching event. Furthermore, the only site that recovered to prebleaching levels received most of these immigrants. We conclude that the genetic structure of this brooding coral reflects its highly opportunistic life history, in which prolific, philopatric recruitment is occasionally supplemented by exogenously produced larvae.

BRCA1 promoter deletions in young women with breast cancer and a strong family history: a population-based study

Women diagnosed with breast cancer before the age of 40 years who have a strong family history of breast and/or ovarian cancer were selected from an Australian population-based case-control-family study for large deletion screening within the BRCA1 promoter. Deletions within the BRCA1 promoter region are usually not detected by the methods applied in routine clinical mutation detection strategies. Fifty-one of the 66 women (77%) who met our inclusion criteria were tested for promoter deletions using linkage disequilibrium analysis of two BRCA1 polymorphic sites (C/G1802 and Pro871Leu) and multiplex ligation-dependent probe amplification. Two cases of BRCA1 promoter deletion involving exons 1A-2 and exons 1A-23 were detected. The morphology of the breast cancers arising in these women with BRCA1 promoter deletions was consistent with the morphology associated with other germline BRCA1 mutations. Large genomic deletions that involve the promoter regions of BRCA1 make up 20% (2/10) of all known BRCA1 mutations in this group of young women with a strong family history of breast and ovarian cancer. Our data support the inclusion of testing for large genomic alterations in the BRCA1 promoter region in routine clinical mutation detection within BRCA1.

Low somatic K-ras mutation frequency in colorectal cancer diagnosed under the age of 45 years

Somatic mutation of K-ras is known to be a common event in colorectal cancer tumourigenesis however its association with age at onset has not been widely explored. In this study, we have analyzed tumours from a population-based study of colorectal cancer diagnosed before the age of 45 years, in which cases had been previously screened for germ-line mismatch repair gene mutations and for microsatellite instability. We used a micro-dissection and sequencing approach to search for somatic K-ras mutations in codons 12, 13 and 61 in 101 early-onset colorectal cancers. Six (6%) somatic K-ras mutations were detected; five in codon 12 (4 G>T transitions and 1 G>A) and one in codon 13 (G>A transition). All codon 12 mutations were identified in microsatellite stable tumours and the codon 13 mutation was identified in a MSI-high tumour. Four cases with K-ras mutations had no reported family history of colorectal cancer and two had some family history of colorectal cancer. None were known to carry a germ-line mutation in hMSH2, hMLH1, hMSH6 or hPMS2. The role of somatic K-ras mutations in early-onset colorectal cancer carcinogenesis appears to be minor, in contrast to its significant role in colorectal cancer of later age of onset.

Type and frequency of peripheral nerve injuries encountered in a clinical neurophysiology laboratory

Clinical and electrophysiologic findings on 136 patients (39 women and 97 men; mean age = 33.2 years) with traumatic peripheral nerve injuries were reviewed. Motor vehicular collisions (MVCs) caused 39.7% and gunshot wounds (GSWs) produced 32.4% of the nerve injuries studied. Other factors such as falls, lacerations, work-related injuries, knife wounds, and blunt traumas produced the remaining 27.9% of the nerve injuries in the study group. Peripheral nerves of the upper limbs (79.6%) were disproportionately damaged in MVCs compared with those of the lower limbs (20.4 %). In MVCs, the brachial plexus was involved in 37.0% and radial nerve in 22.2% of the cases. Patients with GSWs were predominantly men (88.6%) and slightly younger (mean age = 28.7 years). The frequencies of peripheral nerve injuries to the upper extremities (52.3%) and lower extremities (45.5%) were nearly similar in GSWs. The sciatic nerve was involved in 34.1% of GSWs, followed by the ulnar nerve (22.7%).

Use of molecular tumor characteristics to prioritize mismatch repair gene testing in early-onset colorectal cancer

PURPOSE

The relationships between mismatch repair (MMR) protein expression, microsatellite instability (MSI), family history, and germline MMR gene mutation status have not been studied on a population basis.

METHODS

We studied 131 unselected patients with colorectal cancer diagnosed younger than age 45 years. For the 105 available tumors, MLH1, MSH2, MSH6, and PMS2 protein expression using immunohistochemistry (IHC) and MSI were measured. Germline DNA was screened for hMLH1, hMSH2, hMSH6, and hPMS2 mutations for the following patients: all from families fulfilling the Amsterdam Criteria for hereditary nonpolyposis colorectal cancer (HNPCC); all with tumors that were high MSI, low MSI, or that lacked expression of any MMR protein; and a random sample of 23 with MS-stable tumors expressing all MMR proteins.

RESULTS

Germline mutations were found in 18 patients (nine hMLH1, four hMSH2, four hMSH6, and one hPMS2); all tumors exhibited loss of MMR protein expression, all but one were high MSI or low MSI, and nine were from a family fulfilling Amsterdam Criteria. Sensitivities of IHC testing, MSI (high or low), and Amsterdam Criteria for MMR gene mutation were 100%, 94%, and 50%, respectively. Corresponding positive predictive values were 69%, 50%, and 75%.

CONCLUSIONS

Tumor IHC analysis of four MMR proteins and MSI testing provide a highly sensitive strategy for identifying MMR gene mutation-carrying, early-onset colorectal cancer patients, half of whom would have been missed using Amsterdam Criteria alone. Tumor-based approaches for triaging early-onset colorectal cancer patients for MMR gene mutation testing, irrespective of family history, appear to be an efficient screening strategy for HNPCC.

Chemotherapy of an experimental Fusobacterium (Sphaerophorus) necrophorum infection in mice

An experimental animal model for testing antibiotics in vivo against Fusobacterium (Sphaerophorus) necrophorum has been developed. It incorporates the subcutaneous injection of the bacteria into mice followed by intraperitoneal administration of the antibiotic at 24, 48, 72, and 96 h. Mean effective dose values are based on the number of survivors 21 days after challenge. Tetracycline was the most effective drug tested, with a mean effective dose of 5.0 mg/kg, compared with mean effective dose values of 11.1 for clindamycin, 11.8 for penicillin-G, and 52.9 for lincomycin.

A demographic approach to monitoring the health of coral reefs

Inshore coral reefs adjacent to the wet tropics in North Queensland, Australia, are regularly exposed to flood plumes from coastal river systems. Changes in the nature of these plumes have been linked to the declining health of coral reefs in the region. The effect of flood plumes on the health of inshore corals was investigated by quantifying aspects of the demography of populations of corymbose and digitate Acropora at three groups of Island reefs along a gradient of exposure and decreasing water quality (High Island >Frankland's >Fitzroy). The size-structures of colonies, the rates of sexual recruitment, and the growth and survival of juveniles, all varied among the Island reefs. Juvenile and adult sized colonies were far more abundant at the Fitzroy Island reefs, than at the High or Frankland Island reefs that were more exposed to flood plumes. Additionally, there were up to eight times as many sexual recruits at the Fitzroy Island reefs, compared with the High Island reefs. However, the rates of growth and survival of the juvenile sized corals at the Fitzroy Island reefs were lower than at the more exposed reefs. The comparatively low abundance of adult corals at the exposed reefs is most likely due to their histories of disturbance from crown-of-thorns and coral bleaching, but the lack of subsequent recovery due to their low levels of larval recruitment. If a stock-recruitment relationship is typical for these groups of reefs, then the low rates of recruitment may be linked to the low density of adult colonies. Alternately, direct or indirect effects of chronic exposure to poor water quality may have resulted in less suitable substrata for larval settlement. We discuss these results and provide examples of how information about population structure and dynamics can be used in simple matrix models to quantify the current and future health of populations of corals under various scenarios.

Community acquired staphylococcal pulmonary valve endocarditis in non-drug users: case report and review of the literature

Right sided endocarditis usually involves the tricuspid valve, predominantly in intravenous drug users. It is also occasionally acquired in hospital as a result of contaminated intravascular devices. Isolated infection of the pulmonary valve is rarely seen. A case of community acquired Staphylococcus aureus pulmonary valve endocarditis that caused diagnostic confusion is reported. This infection occurred in a patient with no history of intravenous drug abuse and a previously structurally normal heart.

Hypotensive resuscitation using a polymerized bovine hemoglobin-based oxygen-carrying solution (HBOC-201) leads to reversal of anaerobic metabolism

BACKGROUND

Traditional resuscitation regimens have been recently challenged. This study evaluates hypotensive resuscitation with a hemoglobin-based oxygen-carrying (HBOC) solution after severe hemorrhage in a porcine model. We hypothesized that HBOC-201 restores tissue perfusion at a lower mean arterial pressure than standard resuscitation fluids.

METHODS

Yorkshire swine (55-65 kg, n = 30), were rapidly hemorrhaged to a mean arterial pressure (MAP) of 30 mm Hg, maintained hypotensive for 45 minutes, and randomized into groups. Group I was resuscitated with an HBOC solution to a MAP of 60 mm Hg. Groups II and III were resuscitated to a MAP of 80 mm Hg with lactated Ringer's solution (LR) alone or LR (40 mL/kg) followed by shed blood, respectively. Group IV was resuscitated with shed blood alone to a MAP of 60 mm Hg. Group V received an HBOC solution to a MAP of 50 mm Hg. Hemodynamic variables, Swan-Ganz parameters, blood gas samples, and lactate levels were followed for 5 hours. Data were analyzed by analysis of variance/Duncan multiple range test.

RESULTS

There were no significant differences in mortality between any groups. Groups I, IV, and V had lower (p < 0.05) cardiac output, pulmonary artery wedge pressure, and MAP than either group II or group III. Svo2 was significantly lower in the HBOC groups. There were no significant differences in arterial pH or lactate between groups I, III, and IV. Lactate levels, base excess, and arterial pH were significantly worse in the LR-alone and HBOC-50 groups.

CONCLUSION

Hypotensive resuscitation with HBOC-201 at a MAP of 60 mm Hg after a controlled hemorrhage in swine provides sufficient tissue perfusion and oxygen delivery to reverse anaerobic metabolism on the basis of global physiologic markers despite continued hypotension, hypovolemia, and low cardiac output.

Children's artistic responses to musical intervals

In one experiment, White South African boys drew pictures in response to four musical intervals. In the second, the subjects were of both sexes and drawn from White, urban Black, and rural Black populations. Six intervals were used. Drawing content was similar cross-culturally. Consonances were perceived as generally positive; dissonances, generally negative. There was also an activity dimension. Children in a lower grade drew more concrete pictures than did those in a higher grade, regardless of age. Even young listeners were fairly consistent in their responses. This suggests that perception of musical meaning is a universal rather than culturally based phenomenon.

Induced defenses in response to an invading crab predator: an explanation of historical and geographic phenotypic change

The expression of defensive morphologies in prey often is correlated with predator abundance or diversity over a range of temporal and spatial scales. These patterns are assumed to reflect natural selection via differential predation on genetically determined, fixed phenotypes. Phenotypic variation, however, also can reflect within-generation developmental responses to environmental cues (phenotypic plasticity). For example, water-borne effluents from predators can induce the production of defensive morphologies in many prey taxa. This phenomenon, however, has been examined only on narrow scales. Here, we demonstrate adaptive phenotypic plasticity in prey from geographically separated populations that were reared in the presence of an introduced predator. Marine snails exposed to predatory crab effluent in the field increased shell thickness rapidly compared with controls. Induced changes were comparable to (i) historical transitions in thickness previously attributed to selection by the invading predator and (ii) present-day clinal variation predicted from water temperature differences. Thus, predator-induced phenotypic plasticity may explain broad-scale geographic and temporal phenotypic variation. If inducible defenses are heritable, then selection on the reaction norm may influence coevolution between predator and prey. Trade-offs may explain why inducible rather than constitutive defenses have evolved in several gastropod species.

Psychology without p values. Data analysis at the turn of the 19th century

Although the fledgling psychology of 100 years ago was assertively empirical, there were no inferential statistics to guide psychologists' data analyses. However, 19th-century developments had left psychology with a rich array of techniques for analyzing and presenting data, some of which remain underutilized today. These include comparisons across replications, within-subject designs, reanalysis of data, analyses of factorial designs, and especially the use of tables and graphs. As the merits of hypothesis-testing statistics are debated at the turn of the 21st century, the history of data-handling practices can remind psychologists that there are many ways to overcome the current uniformity of statistical practice.

Pseudotumor cerebri secondary to intermediate-dose cytarabine HCl

OBJECTIVE

To describe a case of pseudotumor cerebri associated with the administration of intermediate-dose cytarabine.

CASE SUMMARY

An 11-year-old Hispanic boy with acute myeloblastic leukemia developed symptoms of pseudotumor cerebri (headache, diplopia, photophobia, nausea, vomiting) after receiving chemotherapy including cytarabine. The patient improved after a lumbar puncture and treatment with prednisone and acetazolamide, and is now asymptomatic.

DISCUSSION

Pseudotumor cerebri is a condition usually associated with obese women of child-bearing age. Case reports in pediatric patients are unusual. Several medications have been implicated in causing pseudotumor cerebri, including antimicrobials (tetracycline, naladixic acid), amiodarone, lithium carbonate, vitamin A and its derivatives, growth hormone, and corticosteroids. Chemotherapy agents reported to cause pseudotumor cerebri include busulfan with cyclophosphamide, and the combination of vinblastine, cisplatin, and bleomycin. Most of the information on medication-induced pseudotumor cerebri is in the form of case reports. Different mechanisms for causing this condition have been offered for individual medications. Most of these explanations involve fluid imbalance or interference with the Na+/K+ adenosine triphosphatase pump. Controlled studies are difficult because this condition is an unpredictable and rare occurrence. Cytarabine has frequently been associated with neurologic toxicities, but few reports of pseudotumor cerebri can be found.

CONCLUSIONS

The exact cause of pseudotumor cerebri in this patient is unknown, but cytarabine seems a likely cause. The mechanism by which cytarabine could cause this reaction is unclear.

Audit of cardiac catheterisation in a district general hospital: implications for training

OBJECTIVE

To assess complications of diagnostic cardiac catheterisation in a non-surgical centre by review of the first three years' experience and audit of 2804 diagnostic left heart procedures.

DESIGN

Analysis of a prospective database of cardiac catheter procedures.

SETTING

District general hospital without available on site cardiac surgery.

RESULTS

The rate of major complications of cardiac catheterisation was 0.07%. Mortality was 0. 07%, and the rate of arterial complications (requiring surgical repair) was 0.24% for brachial arteries and 0.17% for femoral. These results are comparable to those reported from national and international surgical centres.

CONCLUSION

A diagnostic cardiac catheterisation service can be offered in non-surgical hospitals without an increased risk to patients. It highlights the relevance of training in angioplasty and questions the appropriateness of starting preliminary invasive cardiology training of specialist registrars in district general hospitals.

Recovery of Claw Size and Function Following Autotomy in Cancer productus (Decapoda: Brachyura)

We examined recovery of claw size and function following autotomy in red rock crabs Cancer productus. We also tested for costs of regeneration to growth and documented the frequency of claw injury in C. productus populations in Barkley Sound, Canada. Field and laboratory results indicated that crabs required at least three molts to recover a full-length cheliped. For injured crabs, regenerating claws were significantly less powerful than contralateral, normal (i.e., uninjured) claws even two instars after autotomy. Greater mechanical advantage in normal claws of injured (versus uninjured) crabs, however, suggests some morphological response by the remaining normal claw to increased exercise. Despite this compensatory response, our experiments indicate that injured crabs remain at a significant disadvantage while foraging. After adjusting for differences in propodus length, both regenerating and normal claws of injured crabs delivered significantly lower crushing forces than did claws of intact crabs. Energetic costs, in the form of reduced body size increase at the molt, were detected only for crabs regenerating both claws. High incidences of single claw loss in C. productus in Barkley Sound, together with our experimental data, suggest that much of the population experiences a prolonged foraging handicap following injury.

Disturbance of peripheral microvascular fluid permeability by the onset of atrioventricular asynchrony in patients with programmable pacemakers

BACKGROUND

In vitro and in vivo evidence suggests that atrial natriuretic peptide can enhance fluid flux from intravascular to extravascular compartments. The relevance of this to human pathophysiology remains unclear.

OBJECTIVES

To determine whether a central haemodynamic change associated with increased plasma concentrations of atrial natriuretic peptide produces detectable change in the capillary filtration coefficient in a peripheral microvascular bed.

PATIENTS

12 patients with programmable dual chamber permanent pacemakers.

METHODS

Calf capillary filtration coefficient (using a modified plethysmographic technique) and plasma atrial natriuretic peptide concentrations were measured during atrioventricular synchronous and ventricular pacing.

RESULTS

Atrioventricular asynchrony was associated with higher mean (SD) concentrations of atrial natriuretic peptide (231.9 (123.1) v 53.5 (38.8) pg/ml) and an increased mean (SD) calf capillary filtration coefficient (4.2 (1.1) v 3.6 (1.1) ml/min.mm Hg.100 ml x 10(-3)), but there was no correlation between the magnitude of the change in these variables in individual patients.

CONCLUSIONS

The peripheral capillary filtration coefficient may change in response to altered central haemodynamics. Atrial natriuretic peptide remains one potential candidate mechanism, but other factors are also likely to be involved.

Disturbance of peripheral microvascular function in congestive heart failure secondary to idiopathic dilated cardiomyopathy

OBJECTIVES

Previous studies of peripheral microvascular function in human heart failure have concentrated on changes in flow, and there is little information concerning the impact of heart failure on the principal determinants of transcapillary fluid exchange. This study investigated whether alterations in capillary pressure and microvascular fluid permeability can be detected in subjects with idiopathic dilated cardiomyopathy.

METHODS

Finger nailfold capillary pressure and calf capillary filtration coefficient (CFC) were measured in parallel studies of two overlapping groups of 12 non-oedematous subjects with idiopathic dilated cardiomyopathy and mild to moderate heart failure and in age- and sex-matched healthy controls. Capillary pressure was measured by direct cannulation using an electronic resistance feedback servonulling technique, and CFC by mercury-in-silastic strain gauge plethysmography using a modification of the technique which avoids assumptions concerning isovolumetric venous pressure.

RESULTS

Following correction for differences in skin temperature, capillary pressure was lower in the subjects with heart failure (P = 0.02). Both CFC and isovolumetric venous pressure were greater in the subjects with heart failure than in controls (3.4 +/- 0.9 vs. 2.6 +/- 0.7 ml.min-1.mmHg-1.100 ml-1, P = 0.03; 27.1 +/- 8.4 vs. 17.2 +/- 7.2 mmHg, P = 0.01).

CONCLUSIONS

These data suggest that factors other than changes in arterial inflow and venous outflow pressures are likely to play an important role in the disruption of microvascular homeostasis which occurs in heart failure. Changes in capillary hydraulic conductance may contribute to the pathogenesis of oedema.

The role of the leader sequence coding region in expression and assembly of bacteriorhodopsin

Bacterio-opsin is made as a precursor in Halobacterium halobium, which has 13 additional residues at the amino terminus. The codons for these residues have been proposed to form a hairpin structure in the mRNA and play a role in ribosome binding; the leader peptide sequence also has been proposed to have a role in membrane insertion of bacteriorhodopsin (BR). We have made mutations in the bop gene region coding for the leader sequence and expressed the mutant genes in an H. halobium mutant lacking wild-type BR. The leader sequence coding region was found to be important for the stability of the mRNA and for its efficient translation. Single base substitutions in this region that did not affect the amino acid sequence caused significant reductions in protein expression. Deletion of the leader region resulted in unstable mRNA and almost no BR production. Introduction of a new ribosome-binding sequence within the coding region of the mature protein restored mRNA stability and some protein expression. Protein made without the leader peptide was properly assembled in the membrane.

Quantitative coronary cineangiography for the study of atherosclerosis

Angiography is the definitive procedure for characterising the extent and course of coronary artery disease. We describe the methodology required to measure, with optimal resolving power, angiographic changes in coronary artery disease. We utilised recent technological developments in image digitization, storage and analysis. The measures of change quantified both diffuse and focal atherosclerosis. Frames from angiographic cine films were digitized at high resolution (1024 x 1024 pixels, 8 bit grey scale) and archived on optical disk. Four radiographic projections were stored to ensure good visualization of as many as possible of a set of ten major arterial segments. Edges of segments and catheter were automatically delineated by computer using a dynamic programming algorithm involving a cost function which contained terms based on edge strength and on continuity. For every digitized radiographic projection, delineation was repeated in three adjacent frames, to improve precision. Edge points for each coronary segment were stored on disk. From these we computed the mean width along the segment (pixels). Scaling to obtain the Mean Absolute Width of the Segment (MAWS, mm) was achieved using catheter dimensions known from micrometry, systematic error due to imaging system line-spread function being corrected using data from computer simulations and phantom studies. Correction for geometric image intensifier distortion was also applied. We used the methodology in a randomized, controlled trial of the effect of lipid-lowering therapy, the St Thomas' Atherosclerosis Regression Study. The fundamental measure of change of disease in each segment was the change in MAWS (delta MAWS). Using in-vitro and in-vivo studies we established that the overall resolving power for one segment delta MAWS was 0.10 mm at 2 mm width and 0.14 mm at 4 mm width. Subsidiary end-points were the change (delta) in minimum absolute width of segment (MinAWS), edge irregularity index (EII) and percent diameter stenosis (%DS). Delta%DS (the conventional angiographic measure of coronary disease) was significantly correlated with change in all indices, closest correlation being seen with delta EII (r = 0.94, p < 0.001).

Postural vasoconstrictor response in human heart failure

In order to study whether posturally induced vasoconstriction is impaired in subjects with heart failure, laser Doppler fluximetry was used to measure blood flow in the cutaneous microvascular bed of the foot at rest and during passive lowering of the extremity below heart level, in subjects with idiopathic dilated cardiomyopathy and in healthy controls. Two sites were studied: the toe pulp where arteriovenous anastomoses are numerous and the dorsum of the foot where such anastomoses are absent. Despite demonstrating a marked reduction in cutaneous blood flow at rest at each site [dorsum 3.0 AU (1.8-4.5) [median (range)] in heart failure patients vs 4.5 AU (1.8-31.6) in controls; toe 8.7 AU (3.1-33.5) in heart failure vs. 44.7 AU (5.2-280.0) in controls, p < 0.01], the results suggest that in non-oedematous subjects with severe left ventricular dysfunction there is no major disturbance of the postural vasoconstrictor response, either at a site rich in highly innervated anastomoses [43.6% (14.5-89.4) vs. 43.7% (15.6-91.1)] or in a site with few such anastomoses [79.7% (39.6-92.3) vs 69.6% (10.1-94.9)].

Xenopus interspersed RNA families, Ocr and XR, bind DNA-binding proteins

Interspersed RNA makes up two-thirds of cytoplasmic polyadenylated RNA in Xenopus and sea urchin eggs. Although it has no known function, previous work has suggested that at least one family of interspersed RNA, XR, binds Xenopus oocyte proteins, and can influence the rate of translation. We have used two Xenopus repeat families, Ocr and XR, to explore their protein binding abilities. Ocr RNA binds the same pattern of highly abundant oocyte proteins that XR RNA binds, which are believed to be messenger ribonucleoprotein (mRNP) particle proteins. In addition, we show that Ocr RNA binds the Oct-60 protein, a member of the POU-domain family of transcription factors found in Xenopus oocytes. Using a 32 base pair sequence from the XR repeat in a DNA affinity column two proteins were isolated, 66 kDa and 92 kDa, that together form a complex with XR DNA. One of these proteins (92 kDa) also binds XR RNA. We suggest that the role of at least a subset of interspersed RNAs in development may be to bind, and sequester in the cytoplasm, DNA-binding proteins until the end of oogenesis.

Evidence that XR family interspersed RNA may regulate translation in Xenopus oocytes

It has been shown that about two thirds of Xenopus oocyte or sea urchin egg cytoplasmic poly(A)+ RNA contains interspersed repetitive sequences. The functional significance of this interspersed RNA has remained unknown. Here the function of a subfamily of interspersed RNA (XR family; McGrew and Richter, 1989: Dev Biol 134:267-270) in Xenopus oocytes was studied. We found that the elimination of T7 XR (one of the two complementary strands of the XR repeat) interspersed RNA by complementary oligodeoxynucleotides significantly inhibited protein synthesis. On the other hand, the injection of in vitro synthesized T7 XR RNA stimulated translation. Moreover, the insertion of the T7 XR RNA sequence into globin mRNA repressed the translation of the globin mRNA. In order to explain these results, we analyzed interactions between the XR interspersed RNA and oocyte proteins. We found that the major XR RNA binding proteins were p56 and p60, which could be the known mRNA "masking" proteins that bind mRNA and inhibit translation. Further, a 42 kD protein has been identified that appears to bind T7 XR RNA relatively specifically, although it interacts with mRNA with a lower affinity. Based on all of these data, we have proposed that interspersed RNA may be involved in regulating translation by competing with mRNA to interact with certain proteins that can regulate translation.

Xenopus Gq alpha subunit activates the phosphatidylinositol pathway in Xenopus oocytes but does not consistently induce oocyte maturation

We cloned the Xenopus laevis form of Gq alpha subunit to study its effects on oocyte maturation. Injection of Xenopus Gq alpha mRNA into stage 6 oocytes activated the phospholipase C/phosphatidylinositol pathway. The oocyte membrane became permeable to calcium ions and was able to generate transient inward currents (T(in)), due to the opening of Ca(2+)-dependent Cl- channels. The T(in) amplitude developed over several hours and disappeared by 24 hr. Diacylglycerol levels were found to parallel the appearance and disappearance of the T(in). The concurrent decline of T(in) values and diacylglycerol was not due to a failure in the synthesis of Gq alpha protein, which was produced continuously for > 24 hr. After Xenopus Gq alpha mRNA injection, germinal vesicle breakdown (GVBD) was variable (0-100%) in stage 6 oocytes, whereas none of the stage 4 oocytes underwent GVBD. In contrast, stage 6 oocytes injected with mRNA encoding the Go alpha G protein consistently underwent GVBD but did not acquire T(in). Our results show that activation of phospholipase C is not an absolute requisite for the induction of maturation, although in oocytes of some frogs phospholipase C activation can trigger a pathway to GVBD.

In vivo storage of XR family interspersed RNA in Xenopus oocytes

Interspersed RNA is an abundant class of cytoplasmic poly(A)+ RNA which contains repetitive elements within mostly heterogeneous single copy sequences. In spite of its quantitative importance in oocytes or eggs (two-thirds of the total poly(A)+ RNA), very little is known about its synthesis, its interaction with other molecules, and its functional significance. Here, we analysed a prevalent family of interspersed RNA (XR family) during Xenopus oogenesis. We found that XR interspersed RNA, unlike extracted interspersed RNA, did not form RNA duplexes in vivo. In small oocytes (stage III), XR RNA interacted with proteins forming rapidly sedimenting ribonucleoprotein particles (RNPs) with a median sedimentation constant of 80S. However, towards the end of oogenesis (stage VI), these XR RNPs changed into smaller particles with a median sedimentation constant of 40S. By analysing the proteins associated with XR RNA sequence, we have identified a 42 kilodalton protein in small oocytes, which was replaced by a 45 kilodalton protein at stage V of oogenesis.

Differential accumulation of mRNA and interspersed RNA during Xenopus oogenesis and embryogenesis

Xenopus oocyte cytoplasmic poly(A)+ RNA has been shown to include two major complex classes: mRNA and interspersed RNA. The former is defined by its translatability, while the latter consists of non-translatable repeat-containing transcripts with unknown functions. In this study we compared the accumulation patterns of total mRNA and a subfamily of interspersed RNA, the XR family (McGrew & Richter, 1989, Dev. Biol. 134, 267-70). The results showed that the XR interspersed RNA level continued to increase throughout oogenesis, while the total mRNA level reached a peak at late stage II and then decreased as much as 40% between stage II and stage VI of oogenesis. In addition we have found that, like mRNA, only about half of the non-translatable XR interspersed RNA underwent deadenylation at oocyte maturation. This result suggested that about half of the interspersed RNA, like certain mRNAs, also contains the U-rich element to protect it from the automatic deadenylation, implying the poly(A) tail of interspersed RNA may play a role during early development.

The peripheral microcirculation in atrial fibrillation: preservation of capillary pressure and filtration coefficient

OBJECTIVE

The aim was to assess whether atrial fibrillation results in disturbances of capillary pressure and capillary filtration coefficient in man.

METHODS

Finger nailfold capillary pressure and calf capillary filtration coefficient were measured in subjects in atrial fibrillation and in matched healthy controls in sinus rhythm. Capillary pressure was measured by direct cannulation using an electronic resistance feedback servonulling technique, and capillary filtration coefficient by mercury-in-Silastic strain gauge plethysmography using a technique believed not to invoke the venoarteriolar response.

RESULTS

Mean capillary pressure did not differ significantly between subjects in atrial fibrillation and those in sinus rhythm [18.4(SD 5.1) mm Hg in atrial fibrillation v 18.0(2.9) mm Hg in sinus rhythm]. In a subgroup of patients restored to sinus rhythm (n = 7) by dc cardioversion there was no significant alteration in capillary pressure [15.3(4.2) mm Hg v 16.6(2.8) mm Hg]. Capillary filtration coefficient was also similar in subjects in atrial fibrillation to that in healthy controls in sinus rhythm [2.81(0.65) kfu in atrial fibrillation v 2.87(0.69) kfu in sinus rhythm].

CONCLUSIONS

These data would suggest that under resting conditions autoregulatory mechanisms are able to preserve microvascular homeostasis despite the central changes associated with atrial fibrillation.

Capillary pulse waveform in aortic stenosis

The importance of the dynamic nature of perfusion pressure within the peripheral microcirculation is increasingly recognised. Capillary pressure is determined not only by arterial inflow pressure, but is also subject to a variety of local and systemic influences which have been shown to affect both mean pressure and the capillary pulse waveform. To what extent changes in central pulse waveform influence capillary pressure has yet to be determined. By using a dynamic technique of capillary pressure measurement in human subjects with aortic stenosis, we have been able to show that the characteristics of the pulse waveform typically associated with large vessels in this condition are also readily detectable at a capillary level despite local influences. However, changes in the rate of pulse wave transmission described in large arteries were not apparent at a microvascular level. Unlike mean capillary pressure and capillary pulse pressure, pulse waveform in the capillary mimics central haemodynamics.

Duration comparison: relative stimulus differences stimulus age, and stimulus predictiveness

Under a psychophysical trials procedure, pigeons were presented with a red light of one duration followed by a green light of a second duration. Eight geometrically spaced base durations were paired with one of four shorter and four longer durations as the alternate member of a duration pair, with different pairs randomly intermixed. One choice was reinforced if red had lasted longer than green, and a second choice was reinforced if green had lasted longer. Performance was compared when all the base durations and their pair members were included (entire-range condition) or when only the four longest base durations and their comparison durations (restricted-range condition) were used. Discrimination sensitivity decreased for longer duration pairs under both conditions, supporting a memory-based account. Sensitivity was lower under the restricted-range condition. Under both conditions, a bias to report "green as longer" increased as the second green duration increased. Bias changed as a matching function of the green-duration predictiveness of the correct choice. The results are related to a quantitative model of timing and remembering proposed by Staddon.

Removing anchorage-dependent cells from culture flasks

We have described an inexpensive and simple method for removal of monolayered cells from tissue culture flasks that, when combined with the reusable procedure of Shepard and Hartmann (2), will save both time and money in laboratories on a limited budget or that do not desire to use a rubber policeman.

Continuity of care through nursing case management of the chronically ill child

In the care of the chronically ill or disabled child, continuity of care between hospital and home must be prompt and continuous. In our myelomeningocele clinic, continuity of care is maintained through a nursing case management system. Our definition of case management is derived from the definition of service coordination made by the Ohio State Bureau for Children with Medical Handicaps. The service coordinator is a CNS who works for health care coordination by bringing together all health care services that are needed for a child with a disabling condition. We describe the aspects of that care coordination, including a thorough definition of our nursing case management process.

Low frequency oscillations in pulmonary arterial pressure in chronic heart failure

Spontaneous, sustained low frequency oscillations of pulmonary arterial pressure were observed in 8 patients with moderate to severe chronic heart failure during recordings of pulmonary arterial pressure of 8.6 to 48 hours duration. The oscillations (frequency range 0.015 to 0.035 Hz) had a distinct peak from and lower frequency range than respiration (0.2 to 0.6 Hz) and heart rate (0.8 to 1.9 Hz). They were present from 42% to 82% of the recording time with an amplitude varying from undetectable to a maximum range from 5.3 mm Hg to 19.7 mm Hg. When detectable, the mean amplitude of the low frequency oscillations of pulmonary arterial pressure ranged from 1.2 +/- 1.2(SD) mm Hg to 4.3 +/- 3.3 mm Hg. These oscillations are lower in frequency than the low frequency component usually described in recordings of systemic arterial pressure and heart rate in normal subjects, and are closer to the very low frequency rhythms described in severe chronic heart failure and Cheyne Stokes respiration.

To cure those afflicted with the disease of insanity: Thomas Bakewell and Spring Vale Asylum

Thomas Bakewell was a prominent, and rather colourful, lay proprietor of a private lunatic asylum in the early nineteenth century. He has perhaps been rather overlooked in the developing history of psychiatry and of the asylum. He wrote quite widely on mental disorder. His first book appeared in 1805. He later produced another, followed by numerous articles in popular literary journals. In the 1820s he became something of a 'popular psychiatrist'. Bakewell believed that insanity was curable, if treated properly and early enough. The treatment system he developed combined a medical approach, which was directed mainly at the bowels, with a fairly sophisticated 'moral treatment'. Spring Vale was opened in 1808, and was designed to enshrine Bakewell's treatment system. After some years of difficulty, it became a commercially successful venture. Despite his achievements at Spring Vale and his extensive writings, however, Bakewell never really succeeded in his goal of convincing public opinion and the legislature that his 'system' ought to be adopted as the model of good practice.