Association of prior treatment with nitrogen-containing bisphosphonates on outcomes of COVID-19 positive patients

COVID-19 infection has resulted in significant morbidity and mortality globally, especially among older adults. Repurposed drugs have demonstrated activity in respiratory illnesses, including nitrogen-containing bisphosphonates. In this retrospective longitudinal study at 4 academic medical centers, we show no benefit of nitrogen-containing bisphosphonates regarding ICU admission, ventilator use, and mortality among older adults with COVID-19 infection. We specifically evaluated the intravenous bisphosphonate zoledronic acid and found no difference compared to oral bisphosphonates.

BACKGROUND

Widely used in osteoporosis treatment, nitrogen-containing bisphosphonates (N-BP) have been associated with reduced mortality and morbidity among older adults. Based on prior studies, we hypothesized that prior treatment with N-BP might reduce intensive care unit (ICU) admission, ventilator use, and death among older adults diagnosed with COVID-19.

METHODS

This retrospective analysis of the PCORnet Common Data Model across 4 academic medical centers through 1 September 2021 identified individuals age >50 years with a diagnosis of COVID-19. The composite outcome included ICU admission, ventilator use, or death within 15, 30, and 180 days of COVID-19 diagnosis. Use of N-BP was defined as a prescription within 3 years prior. ICU admission and ventilator use were determined using administrative codes. Death included both in-hospital and out-of-hospital events. Patients treated with N-BP were matched 1:1 by propensity score to patients without prior N-BP use. Secondary analysis compared outcomes among those prescribed zoledronic acid (ZOL) to those prescribed oral N-BPs.

RESULTS

Of 76,223 COVID-19 patients identified, 1,853 were previously prescribed N-BP, among whom 559 were prescribed ZOL. After propensity score matching, there were no significant differences in the composite outcome at 15 days (HR 1.22, 95% CI: 0.89-1.67), 30 days (HR 1.24, 95% CI: 0.93-1.66), or 180 days (HR 1.17, 95% CI: 0.93-1.48), comparing those prescribed and not prescribed N-BP. Compared to those prescribed oral N-BP, there were no significant differences in outcomes among those prescribed ZOL.

CONCLUSION

Among older COVID-19 patients, prior exposure to N-BP including ZOL was not associated with a reduction in ICU admission, ventilator use, or death.

Platelets trigger perivascular mast cell degranulation to cause inflammatory responses and tissue injury

Platelet responses have been associated with end-organ injury and mortality following complex insults such as cardiac surgery, but how platelets contribute to these pathologies remains unclear. Our studies originated from the observation of microvascular platelet retention in a rat cardiac surgery model. Ensuing work supported the proximity of platelet aggregates with perivascular mast cells (MCs) and demonstrated that platelet activation triggered systemic MC activation. We then identified platelet activating factor (PAF) as the platelet-derived mediator stimulating MCs and, using chimeric animals with platelets defective in PAF generation or MCs lacking PAF receptor, defined the role of this platelet-MC interaction for vascular leakage, shock, and tissue inflammation. In application of these findings, we demonstrated that inhibition of platelet activation in modeled cardiac surgery blunted MC-dependent inflammation and tissue injury. Together, our work identifies a previously undefined mechanism of inflammatory augmentation, in which platelets trigger local and systemic responses through activation of perivascular MCs.

STIM1 R304W causes muscle degeneration and impaired platelet activation in mice

STIM1 and ORAI1 regulate store-operated Ca²⁺ entry (SOCE) in most cell types, and mutations in these proteins have deleterious and diverse effects. We established a mouse line expressing the STIM1 R304 W gain-of-function mutation causing Stormorken syndrome to explore effects on organ and cell physiology. While STIM1 R304 W was lethal in the homozygous state, surviving mice presented with reduced growth, skeletal muscle degeneration, and reduced exercise endurance. Variable STIM1 expression levels between tissues directly impacted cellular SOCE capacity. In contrast to patients with Stormorken syndrome, STIM1 was downregulated in fibroblasts from Stim1^R304W/R304W mice, which maintained SOCE despite constitutive protein activity. In studies using foetal liver chimeras, STIM1 protein was undetectable in homozygous megakaryocytes and platelets, resulting in impaired platelet activation and absent SOCE. These data indicate that downregulation of STIM1 R304 W effectively opposes the gain-of-function phenotype associated with this mutation, and highlight the importance of STIM1 in skeletal muscle development and integrity.

Erratum: iPS-derived MSCs from an expandable bank to deliver a prodrug-converting enzyme that limits growth and metastases of human breast cancers

[This corrects the article DOI: 10.1038/cddiscovery.2016.64.].

Weight management for adolescents with intellectual and developmental disabilities: Rationale and design for an 18month randomized trial

Adolescents with intellectual and developmental disabilities (IDD) are an underserved group in need of weight management. However, information regarding effective weight management for this group is limited, and is based primarily on results from small, non-powered, non-randomized trials that were not conducted in accordance with current weight management guidelines. Additionally, the comparative effectiveness of emerging dietary approaches, such as portion-controlled meals (PCMs) or program delivery strategies such as video chat using tablet computers have not been evaluated. Therefore, we will conduct an 18month trial to compare weight loss (6months) and maintenance (7-18months) in 123 overweight/obese adolescents with mild to moderate IDD, and a parent, randomized to a weight management intervention delivered remotely using FaceTime™ on an iPad using either a conventional meal plan diet (RD/CD) or a Stop Light diet enhanced with PCMs (RD/eSLD), or conventional diet delivered during face-to-face home visits (FTF/CD). This design will provide an adequately powered comparison of both diet (CD vs. eSLD) and delivery strategy (FTF vs. RD). Exploratory analyses will examine the influence of behavioral session attendance, compliance with recommendations for diet (energy intake), physical activity (min/day), self-monitoring of diet and physical activity, medications, and parental variables including diet quality, physical activity, baseline weight, weight change, and beliefs and attitudes regarding diet and physical activity on both weight loss and maintenance. We will also complete a cost and contingent valuation analysis to compare costs between RD and FTF delivery.

Platelet immunoreceptor tyrosine-based activation motif (ITAM) and hemITAM signaling and vascular integrity in inflammation and development

Platelets are essential for maintaining hemostasis following mechanical injury to the vasculature. Besides this established function, novel roles of platelets are becoming increasingly recognized, which are critical in non-injury settings to maintain vascular barrier integrity. For example, during embryogenesis platelets act to support the proper separation of blood and lymphatic vessels. This role continues beyond birth, where platelets prevent leakage of blood into the lymphatic vessel network. During the course of inflammation, platelets are necessary to prevent local hemorrhage due to neutrophil diapedesis and disruption of endothelial cell-cell junctions. Surprisingly, platelets also work to secure tumor-associated blood vessels, inhibiting excessive vessel permeability and intra-tumor hemorrhaging. Interestingly, many of these novel platelet functions depend on immunoreceptor tyrosine-based activation motif (ITAM) signaling but not on signaling via G protein-coupled receptors, which plays a crucial role in platelet plug formation at sites of mechanical injury. Murine platelets express two ITAM-containing receptors: the Fc receptor γ-chain (FcRγ), which functionally associates with the collagen receptor GPVI, and the C-type lectin-like 2 (CLEC-2) receptor, a hemITAM receptor for the mucin-type glycoprotein podoplanin. Human platelets express an additional ITAM receptor, FcγRIIA. These receptors share common downstream effectors, including Syk, SLP-76 and PLCγ2. Here we will review the recent literature that highlights a critical role for platelet GPVI/FcRγ and CLEC-2 in vascular integrity during development and inflammation in mice and discuss the relevance to human disease.

Concerning the time dependence of the decay rate of 137Cs

The decay rates of eight nuclides ((85)Kr, (90)Sr, (108)Ag, (133)Ba, (137)Cs, (152)Eu, (154)Eu, and (226)Ra) were monitored by the standards group at the Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany, over the time frame June 1999 to November 2008. We find that the PTB measurements of the decay rate of (137)Cs show no evidence of an annual oscillation, in agreement with the recent report by Bellotti et al. However, power spectrum analysis of PTB measurements of a (133)Ba standard, measured in the same detector system, does show such evidence. This result is consistent with our finding that different nuclides have different sensitivities to whatever external influences are responsible for the observed periodic variations.

Adenosine trisphosphate appears to act via different receptors in terminals versus somata of the hypothalamic neurohypophysial system

ATP-induced ionic currents were investigated in isolated terminals and somata of the hypothalamic neurohypophysial system (HNS). Both terminals and somata showed inward rectification of the ATP-induced currents and reversal near 0 mV. In terminals, ATP dose-dependently evoked an inactivating, inward current. However, in hypothalamic somata, ATP evoked a very slowly inactivating, inward current with a higher density, and different dose dependence (EC(50) of 50 μm in somata versus 9.6 μm in terminals). The ATP-induced currents, in both the HNS terminals and somata, were highly and reversibly inhibited by suramin, suggesting the involvement of a purinergic receptor (P2XR). However, the suramin inhibition was significantly different in the two HNS compartments (IC(50) of 3.6 μm in somata versus 11.6 μm in terminals). Also, both HNS compartments show significantly different responses to the purinergic receptor agonists: ATP-γ-S and benzoyl-benzoyl-ATP. Finally, there was an initial desensitisation to ATP upon successive stimulations in the terminals, which was not observed in the somata. These differences in EC(50) , inactivation, desensitisation and agonist sensitivity in terminals versus somata indicate that different P2X receptors mediate the responses in these two compartments of HNS neurones. Previous work has revealed mRNA transcripts for multiple purinergic receptors in micropunches of the hypothalamus. In the HNS terminals, the P2X purinergic receptor types P2X2, 3, 4 and 7 (but not 6) have been shown to exist in AVP terminals. Immonohistochemistry now indicates that P2X4R is only present in AVP terminals and that the P2X7R is found in both AVP and oxytocin terminals and somata. We speculate that these differences in receptor types reflects the specific function of endogenous ATP in the terminals versus somata of these central nervous system neurones.

Associating changes in output behavior with changes in parameter values in spiking and bursting neuron models

Several recent studies have demonstrated that neuronal models allow multiple parameter value solutions for a given output. In the face of this variability of parameter values, what can be learned about neural function through parameter value differences? Here, in two different models, we examine this question by attempting to reconstruct the source of model output changes based on simple statistical analyses of parameter distributions generated by automated searches. We conclude that changes to parameter values or their associated distributions do not reliably reflect the specific mechanisms responsible for a given change in output.

Development and characterization of in vivo flexible electrodes compatible with large tissue displacements

Electrical activity is the ultimate functional measure of neuronal tissue and recording that activity remains a key technical challenge in neuroscience. The mechanical mismatch between rigid electrodes and compliant brain tissue is a critical limitation in applications where movement is an inherent component. An electrode that permits recording of neural activity, while minimizing tissue disruption, is beneficial for applications that encompass both normal physiological movements and those which require consistent recording during large tissue displacements. In order to test the extreme of this range of movement, flexible electrodes were developed to record activity during and immediately following cortical impact in the rat. Photolithography techniques were used to fabricate flexible electrodes that were readily insertable into the brain using a parylene C base and gold conduction lines and contact pads, permitting custom geometry. We found that this electrode configuration retained mechanical and electrical integrity following both durability studies and large movements within the cortex. This novel flexible electrode configuration provides a novel platform for experimentally examining neuronal activity during a range of brain movements.

Human albumin preserves islet mass and function better than whole serum during pretransplantation islet culture

OBJECTIVE

Human islet transplant protocols frequently include a brief period of islet culture before transplantation. Some investigators have suggested that medium supplementation with human serum might quench collagenase activity and provide better culture conditions when compared with human albumin. We studied the effect of whole serum on islet count, islet equivalence, insulin secretion, and DNA content in human islets.

METHODS

Adult human islets isolated from a single pancreas with purity >50% were cultured in identical 150 islet equivalent samples at 37 degrees C using CMRL 1066-based islet medium (Mediatech) supplemented with either 0.5% human albumin or 10% human AB serum. Prior to culture and after 3 days, islets were assessed in vitro using dithizone staining (n = 4), insulin release after static glucose stimulation (n = 8), and DNA content (n = 8).

RESULTS

After 3 days, islet mass (defined by the number of islets and islet equivalents counted after dithizone staining) was better preserved in islets cultured in 0.5% human albumin. Although the stimulation index and total DNA content were similar between groups, islets cultured in human albumin demonstrated greater absolute insulin secretion (p = .02) and insulin secretion per cell (p = .02).

CONCLUSIONS

When used to supplement CMRL 1066-based islet culture medium, human albumin preserves islet mass and secretory capacity better than whole human serum. Human serum offers no advantage in islet preservation or function.

The prevalence of intrahepatic cholestasis of pregnancy in a primarily Latina Los Angeles population

OBJECTIVE

To establish the prevalence of intrahepatic cholestasis of pregnancy (ICP) in a primarily Latina population in the United States.

STUDY DESIGN

Over a period of 16 months, a convenience sample of subjects admitted to labor and delivery in the third trimester was enrolled. Each subject completed a questionnaire rating their severity of pruritus on a numeric scale of 1 to 10. Serum was analyzed via radioimmunoassay for total bile acid concentration. ICP was defined as pruritus score >4 and a total serum bile acid concentration of >or=20 micromol/l. Ethnicity was determined from hospital record demographic data.

RESULTS

All invited participants enrolled in the study. Three hundred and forty subjects were enrolled. Three hundred and sixteen subjects (93%) were identified as Latina. The serum bile acid concentration range for the entire study population was 1 to 580 micromol/l with a mean of 10.4+/-34.9 micromol/l. Twenty-four (7.1%) subjects had a serum bile acid concentration >or=20 micromol/l. A pruritus score >4 was found in 19.7% (67/340). Of the 24 subjects with a bile acid concentration >or=20 micromol/l, 19 also had a pruritus score >4. Thus, the prevalence of ICP in this population was 5.6% (19/340). In subjects with ICP, the mean serum bile acid concentration was 89.5+/-124.0 micromol/l. When controlling for confounders, women with ICP were associated with higher rates of chorioamnionitis (P=0.043) and their fetuses had higher rates of thick meconium (P=0.053).

CONCLUSIONS

The overall prevalence of ICP in this population was 5.6%, 10 to 100 times higher than previously reported data from the United States. Larger studies of perinatal morbidity examining the diagnostic criteria of cholestasis need to be conducted.

Essential role of the persistent sodium current in spike initiation during slowly rising inputs in mouse spinal neurones

Spinal motoneurons, like many neurons, respond with repetitive spiking to sustained inputs. The afterhyperpolarization (AHP) that follows each spike, however, decays relatively slowly in motoneurons. The slow depolarization during this decay should allow sodium (Na+) channel inactivation to keep up with its activation and thus should prevent initiation of the next spike. We hypothesized that the persistent component of the total Na+ current provides the mechanism that generates a rate of rise sufficiently rapid to generate a spike. In large cultured spinal neurons, presumed to be primarily motoneurons, inhibition of persistent sodium current (NaP) by the drug riluzole at low concentrations resulted in a loss of repetitive firing. However, cells remained fully capable of producing spikes to transient inputs. These effects of riluzole were not due to insufficient depolarization, enhancement of the AHP, or sustained Na+ channel inactivation. To further test this hypothesis, computer simulations were performed with a kinetic Na+ channel model that provided greater independent control of NaP relative to transient Na+ current (NaT) than that provided by riluzole administration. The model was tuned to generate substantial NaP and exhibited good repetitive firing to slowly rising inputs. When NaP was sharply reduced without significantly altering NaT, the model reproduced the effects of riluzole administration, inducing failure of repetitive firing but allowing single spikes in response to sharp transients. These results strongly support the essential role of NaP in spike initiation to slow inputs in spinal neurons. NaP may play a fundamental role in determining how a neuron responds to sustained inputs.

Roles of NF-κB and Bcl-2 in Two Differential Modes of Cell Death of Mouse Cortical Collecting Duct Cells

Recent data have implicated nuclear factor-kappaB (NF-kappaB) and Bcl-2 in the regulation of apoptotic and necrotic cell death in various cells. However, mechanisms of their effects on cell death of renal epithelial cells are not clear. First, we investigated the effect of specific inhibition of NF-kappaB and overexpression of Bcl-2 on necrotic cell death induced by hydrogen peroxide or cisplatin in renal collecting duct cells. M-1 cells, which were derived from outer cortical collecting duct, were stably transfected with the non-phosphorylatable mutant of inhibitory-kappaBalpha (I-kappaBalpha) and Bcl-2. Overexpression of I-kappaBalpha and Bcl-2 did not affect cisplatin-induced necrotic cell death, but overexpression of I-kappaBalpha significantly decreased H2O2-induced cell death. Regarding apoptotic cell death induced by cisplatin, serum deprivation and contact inhibition was increased by overexpression of I-kappaBalpha, whereas overexpression of bcl-2 inhibited the apoptotic cell death. I-kappaBalpha overexpression increased Bax expression and decreased cIAP-1 and -2 expression compared to vector-transfected cells, but did not alter SAPK/JNK activity in the presence or absence of cisplatin. NF-kappaB activity was significantly higher in bcl-2-overexpressing cells than in control cells. These data show that activation of NF-kappaB mediates H2O2-induced necrotic injury, but inhibits apoptotic cell death in renal collecting duct cells, and that Bcl-2 selectively protects apoptotic cell death in M-1 cells.

Influence of active dendritic currents on input-output processing in spinal motoneurons in vivo

The extensive dendritic tree of the adult spinal motoneuron generates a powerful persistent inward current (PIC). We investigated how this dendritic PIC influenced conversion of synaptic input to rhythmic firing. A linearly increasing, predominantly excitatory synaptic input was generated in triceps ankle extensor motoneurons by slow stretch (duration: 2-10 s) of the Achilles tendon in the decerebrate cat preparation. The firing pattern evoked by stretch was measured by injecting a steady current to depolarize the cell to threshold for firing. The effective synaptic current (I(N), the net synaptic current reaching the soma of the cell) evoked by stretch was measured during voltage clamp. Hyperpolarized holding potentials were used to minimize the activation of the dendritic PIC and thus estimate stretch-evoked I(N) for a passive dendritic tree (I(N,PASS)). Depolarized holding potentials that approximated the average membrane potential during rhythmic firing allowed strong activation of the dendritic PIC and thus resulted in marked enhancement of the total stretch-evoked I(N) (I(N,TOT)). The net effect of the dendritic PIC on the generation of rhythmic firing was assessed by plotting stretch-evoked firing (strong PIC activation) versus stretch-evoked I(N,PASS) (minimal PIC activation). The gain of this input-output function for the neuron (I-O(N)) was found to be ~2.7 times as high as for the standard injected frequency current (F-I) function in low-input conductance neurons. However, about halfway through the stretch, firing rate tended to become constant, resulting in a sharp saturation in I-O(N) that was not present in F-I. In addition, the gain of I-O(N) decreased sharply with increasing input conductance, resulting in much lower stretch-evoked firing rates in high-input conductance cells. All three of these phenomena (high initial gain, saturation, and differences in low- and high-input conductance cells) were also readily apparent in the differences between stretch-evoked I(N,TOT) and I(N, PASS) and thus could be accounted for by the activation of the dendritic PIC. As a result, stretch-evoked I(N,TOT) and F-I provided an accurate prediction of the overall change in stretch-evoked firing. However, in about half of the low-input conductance cells, the rate of rise of firing in response to stretch was not smoothly graded but instead consisted of a rapid surge. Stretch-evoked I(N,TOT) was always smoothly graded. This suggests that although stretch-evoked I(N,TOT) can be used to predict the overall change in firing, prediction of the dynamics of firing may be less accurate.

Effects of peripheral benzodiazepine receptor ligands on proliferation and differentiation of human mesenchymal stem cells

The peripheral benzodiazepine receptor (PBR) has been known to have many functions such as a role in cell proliferation, cell differentiation, steroidogenesis, calcium flow, cellular respiration, cellular immunity, malignancy, and apoptosis. However, the presence of PBR has not been examined in mesenchymal stem cells. In this study, we demonstrated the expression of PBR in human bone marrow stromal cells (hBMSCs) and human adipose stromal cells (hATSCs) by RT-PCR and immunocytochemistry. To determine the roles of PBR in cellular functions of human mesenchymal stem cells (hMSCs), effects of diazepam, PK11195, and Ro5-4864 were examined. Adipose differentiation of hMSCs was decreased by high concentration of PBR ligands (50 microM), whereas it was increased by low concentrations of PBR ligands (<10 microM). PBR ligands showed a biphasic effect on glycerol-3-phosphate dehydrogenase (GPDH) activity. High concentration of PBR ligands (from 25 to 75 microM) inhibited proliferation of hMSCs. However, clonazepam, which does not have an affinity to PBR, did not affect adipose differentiation and proliferation of hMSCs. The PBR ligands did not induce cell death in hMSCs. PK11195 (50 microM) and Ro5-5864 (50 microM) induced cell cycle arrest in the G(2)/M phase. These results indicate that PBR ligands play roles in adipose differentiation and proliferation of hMSCs.

Nitric oxide in the healing wound: a time-course study

INTRODUCTION

We studied the time course of nitric oxide expression in the healing wound and the cell populations responsible for its synthesis.

METHODS

Twenty four Lewis rats underwent subcutaneous implantation of polyvinyl alcohol sponges. Rats were sacrificed in groups of three on days 1, 3, 5, 7, 10, 14, and 35 after wounding. The conversion of 3H-labeled arginine to 3H-labeled citrulline, with or without N(G)-L-monomethyl-arginine (L-NMMA) in harvested sponges, was measured. Nitrate/nitrite (NOx) in plasma and wound fluid was quantified by Greiss reaction. Inducible nitric oxide synthase (iNOS) gene expression was determined by Northern analysis and reverse transcriptase-polymerase chain reaction (RT-PCR). Inducible NOS was identified in specific wound cell populations by dual-label flow cytometry.

RESULTS

Nitric oxide synthase (NOS) activity peaked at 24 h after wounding (37.7 +/- 0.9 micromol citrulline per milligram sponge), with a steady decline thereafter. Percentage inhibition of NOS activity by l-NMMA was highest on days 1-7 (70-80%). This declined to 50% by day 10 and to 25% by days 14-35. The iNOS gene expression paralleled NOS biochemical activity. RT-PCR confirmed low-level expression up to 10 days after wounding. Plasma NOx levels remained within a narrow range of 22.6 +/- 1.3 to 29.3 +/- 1.5 microM throughout the postwounding period, while corresponding levels in wound fluid (microM) increased steadily from 27 +/- 3.8 on day 1 to 107.2 +/- 10.0 on day 14. Inducible NOS expression was detectable by fluorescence-activated cell sorting in wound macrophages on days 1 and 3 after wounding.

CONCLUSIONS

Our findings suggest maximal NOS activity early in cutaneous wound healing, with sustained production up to 10 days after wounding. NOS biochemical activity was paralleled by iNOS gene expression. Plasma NOx remained constant, while wound fluid NOx increased steadily to peak at day 14. Wound macrophages appear to be a source of nitric oxide production in the early phase of wound healing.

Cisplatin-induced apoptosis by translocation of endogenous Bax in mouse collecting duct cells

cis-platinum(II) (cis-diammine dichloroplatinum; cisplatin) is a potent antitumor compound that is widely used for the treatment of many malignancies. An important side-effect of cisplatin is nephrotoxicity, which results from injury to renal tubular epithelial cells and can be manifested as either acute renal failure or a chronic syndrome characterized by renal electrolyte wasting. Recently, apoptosis has been recognized as an important mechanism of cell death mediating the antitumor effect of cisplatin. This study was undertaken to examine the mechanisms of cell death induced by cisplatin in M-1 cells, which were derived from the outer cortical collecting duct cells of SV40 transgenic mice. Treatment of M-1 cells with high concentrations of cisplatin (0.5 and 1 mM) for 2 hr led to necrotic cell death, whereas a 24-hr treatment with 5-20 microM cisplatin led to apoptosis. Antioxidants protected against cisplatin-induced necrosis, but not apoptosis, indicating that reactive oxygen species play a role in mediating necrosis but not apoptosis induced by cisplatin and that the mechanism of cell death induced by cisplatin is concentration dependent. The low concentrations of cisplatin, which induced apoptosis in M-1 cells, did not affect the expression levels of Bcl-2-related proteins and did not activate c-Jun NH2-terminal kinase (SAPK/JNK). Cisplatin induced the translocation of endogenous Bax from the cytosolic to the membrane fractions and, subsequently, the release of cytochrome c. Overexpression of Bcl-2 blocked cisplatin-induced apoptosis and Bax translocation. These observations suggest that the subcellular redistribution of Bax is a critical event in the apoptosis induced by cisplatin.

System effects of the Kansas Mental Health Reform Act of 1991

This paper analyzes the impact of the Kansas Mental Health Reform Act on client outcomes. The Act is of general interest because it reflects a trial of greater accountability without major changes in financial incentives. It made Community Mental Health Centers [CMHCs] gatekeepers that were accountable for services for adults with severe and persistent mental illnesses. The Act sought reductions in hospitalizations rates, expanded use of community support services, and increased independent living. The structure of the Act and Client Status Reports allow rigorous examination of these outcomes. The number of clients served increased significantly. Even though hospital days fell by 23%, there is no clear evidence that the Act itself reduced hospital days per client. The proportion of community support program clients residing independently rose significantly; the proportion participating meaningfully in the labor market fell. The goals of the Act were realized overall, but the performance of CMHCs varied considerably.

Growth and nutrition of Chinese vegetarian children in Hong Kong

OBJECTIVE

The study investigated the nutritional status of Chinese lacto-ovo-vegetarian children aged 4-14 years.

METHODOLOGY

Dietary intake over 7 days was assessed using a computer program, previously used for a local population-based dietary survey. Anthropometric measurements were made and fasting venous blood was examined for serum lipids, haematological data, iron, vitamin B12 and folate status. Bone mineral density (BMD) of the spine (L2 - L4) was measured as a reflection of calcium status.

RESULTS

Fifty-one lacto-ovo-vegetarians aged 4-14 years were investigated. The mean +/- standard deviation (SD) daily energy intake was 1600 +/- 425 kcal. The mean (+/- SD) daily protein intake was 1.6 +/- 0.6 g/kg bodyweight which met the United States recommended dietary allowance. Compared to that of the local omnivore diet, the vegetarian diet was closer to the recommended healthy diet with lower fat (20-23%), more fibre (5.8-8.7 g/day) and better polyunsaturated to saturated fatty acid ratio (1.0-1.1). Growth and BMD of the vegetarian children were comparable to the general omnivore population. Two children had iron deficiency and two children had anaemia. The calcium status, as reflected by the BMD, was not impaired. Serum folate and vitamin B12 were within the normal range. Six (25%) boys and four (15%) girls were obese. Three boys had hyperlipidaemia.

CONCLUSIONS

A Hong Kong Chinese vegetarian diet appears healthy, providing adequate iron and vitamin B12 nutrition, but the prevalence of obesity was high.

Leaf senescence in rice plants: cloning and characterization of senescence up-regulated genes

To identify senescence-associated genes (SAGs) in rice leaves, senescence was induced by transferring rice seedlings into darkness. Senescence up-regulated cDNAs were obtained by PCR-based subtractive hybridization. Among 14 SAG clones characterized, 11 were found to be associated with both dark-induced and natural leaf senescence. Three clones were associated only with dark-induced leaf senescence. The possible physiological roles of these SAGs during rice leaf senescence are discussed.

Changes in expression of sodium cotransporters and aquaporin-2 during ischemia-reperfusion injury in rabbit kidney

Ischemic renal injury is associated with defects in transport functions of the proximal tubules and urinary concentration ability. To determine whether alterations in expression of various transporter genes contribute to an impairment in renal functions, the expression of various solute transport genes was analyzed in renal cortex and medulla of rabbits with ischemic acute renal failure. Rabbits were subjected to 60 min of renal pedicle clamping followed by 24, 48, or 72 h of reperfusion. Urine volume and glomerular filtration rate were markedly decreased, which were accompanied by an increase in serum creatinine level and fraction Na+ excretion. Glucosuria and phosphaturia were evident during reperfusion periods. These alterations in renal functions were persisted to 72 h after reperfusion. The Na+-dependent uptakes of glucose and phosphate by brush border membrane vesicles were inhibited by 24 h of reperfusion. mRNA levels for Na+-glucose, Na+-phosphate, and Na+-succinate cotransporter analyzed by RT-PCR were not changed by 60 min of ischemia alone, but were significantly reduced by 24 h of reperfusion. mRNA levels for apical Na+-K+-2Cl- cotransporter, NaCl cotransporter, and turea transporter in the medulla were not changed during reperfusion. Protein levels for AQP2 in the medulla, but not AQP1 in the cortex, analyzed by Western blot were significantly reduced at 24 h after reperfusion. These results suggest that reductions in expression of Na+-cotransporter genes in the proximal tubules may be important factors in the impairment in Na+-dependent reabsorption of solutes and that decrease in AQP2 protein may be involved in defect in urinary concentration ability in rabbits with ischemic acute renal failure.