Atlanto-axial infection after acupuncture.

A 67-year-old man presented with neck cellulitis following acupuncture for cervical spondylosis. Blood cultures were positive for methicillin-sensitive Staphylococcus aureus Increased neck pain and bacteraemia prompted MRI, which showed atlanto-axial septic arthritis without signs of infection of the tissues between the superficial cellulitic area and the atlanto-axial joint, thus making direct extension of infection unlikely. It is more likely that haematogenous spread of infection resulted in seeding in the atlanto-axial joint, with the proximity of the arthritis and acupuncture site being coincidental. Acupuncture is a treatment option for some indolent pain conditions. As such, acupuncture services are likely to be more frequently utilised. A history of acupuncture is rarely requested by the admitting doctor and seldom offered voluntarily by the patient, especially where the site of infection due to haematogenous spread is distant from the needling location. Awareness of infectious complications following acupuncture can reduce morbidity through early intervention.

Atlanto-axial infection after acupuncture.

A 67-year-old man presented with neck cellulitis following acupuncture for cervical spondylosis. Blood cultures were positive for methicillin-sensitive Staphylococcus aureus. Increased neck pain and bacteraemia prompted MRI, which showed atlanto-axial septic arthritis without signs of infection of the tissues between the superficial cellulitic area and the atlanto-axial joint, thus making direct extension of infection unlikely. It is more likely that haematogenous spread of infection resulted in seeding in the atlanto-axial joint, with the proximity of the arthritis and acupuncture site being coincidental. Acupuncture is a treatment option for some indolent pain conditions. As such, acupuncture services are likely to be more frequently utilised. A history of acupuncture is rarely requested by the admitting doctor and seldom offered voluntarily by the patient, especially where the site of infection due to haematogenous spread is distant from the needling location. Awareness of infectious complications following acupuncture can reduce morbidity through early intervention.

Identification of genes differentially expressed in T cells following stimulation with the chemokines CXCL12 and CXCL10.

BACKGROUND: Chemokines are involved in many biological activities ranging from leukocyte differentiation to neuronal morphogenesis. Despite numerous reports describing chemokine function, little is known about the molecular changes induced by cytokines. METHODS: We have isolated and identified by differential display analysis 182 differentially expressed cDNAs from CXCR3-transfected Jurkat T cells following treatment with CXCL12 or CXCL10. These chemokine-modulated genes were further verified using quantitative RT-PCR and Western blot analysis. RESULTS: One hundred and forty-six of the cDNAs were successfully cloned, sequenced, and identified by BLAST. Following removal of redundant and non-informative clones, seventeen mRNAs were found to be differentially expressed post treatment with either chemokine ligand with several representing known genes with established functions. Twenty-one genes were upregulated in these transfected Jurkat cells following both CXCL12 and CXCL10, four genes displayed a discordant response and seven genes were downregulated upon treatment with either chemokine. Identified genes include geminin (GEM), thioredoxin (TXN), DEAD/H box polypeptide 1 (DDX1), growth hormone inducible transmembrane protein (GHITM), and transcription elongation regulator 1 (TCERG1). Subsequent analysis of several of these genes using semi-quantitative PCR and western blot analysis confirmed their differential expression post ligand treatment. CONCLUSIONS: Together, these results provide insight into chemokine-induced gene activation and identify potentially novel functions for known genes in chemokine biology.

Functional differences of the PDS gene product are associated with phenotypic variation in patients with Pendred syndrome and non-syndromic hearing loss (DFNB4).

The PDS gene encodes a transmembrane protein, known as pendrin, which functions as a transporter of iodide and chloride. Mutations in this gene are responsible for Pendred syndrome and autosomal recessive non-syndromic hearing loss at the DFNB4 locus on chromosome 7q31. A screen of 20 individuals from the midwestern USA with non-syndromic hearing loss and dilated vestibular aqueducts identified three people (15%) with PDS mutations. To determine whether PDS mutations in individuals with Pendred syndrome differ functionally from PDS mutations in individuals with non-syndromic hearing loss, we compared three common Pendred syndrome allele variants (L236P, T416P and E384G), with three PDS mutations reported only in individuals with non-syndromic hearing loss (V480D, V653A and I490L/G497S). The mutations associated with Pendred syndrome have complete loss of pendrin-induced chloride and iodide transport, while alleles unique to people with DFNB4 are able to transport both iodide and chloride, albeit at a much lower level than wild-type pendrin. We hypothesize that this residual level of anion transport is sufficient to eliminate or postpone the onset of goiter in individuals with DFNB4. We propose a model for pendrin function in the thyroid in which pendrin transports iodide across the apical membrane of the thyrocyte into the colloid space.

Leptin signaling in the hypothalamus of normal rats in vivo.

Leptin has been shown to activate multiple signaling molecules in cultured cells, including Janus kinase-2, STAT (signal transducer and activator of transcription) proteins, and mitogen-activated protein kinase, and to stimulate the DNA-binding activity of STAT3 in mouse hypothalamus. In this study, the activation of candidate leptin signaling molecules in the hypothalamus of normal rats in vivo was investigated. Fasted male Sprague-Dawley rats were injected iv with recombinant murine leptin or vehicle. Plasma leptin concentrations were determined at defined time points, and the phosphorylation of signaling proteins was assessed in hypothalamic lysates. There was a marked increase in plasma leptin concentration at 2 min and a gradual decline by 45 min after leptin injection. Immunoblotting analysis of hypothalamic lysates with a phosphospecific STAT3 antibody demonstrated a time-dependent stimulation of STAT3 tyrosine phosphorylation. STAT3 phosphorylation was first evident at 5 min and was maximal at 30 min after leptin injection. By contrast, leptin did not increase the phosphorylation of Janus kinase proteins, mitogen-activated protein kinase, or STAT1 and -5 despite abundant expression of these signaling molecules in the hypothalamus. These results differ from findings in cultured cells and in vitro systems. It remains unclear how signaling is propagated downstream from the leptin receptor to STAT3, but this may involve novel signaling intermediates.

Gut adaptation and the insulin-like growth factor system: regulation by glutamine and IGF-I administration.

Intestinal adaptation after extensive small bowel resection in rats is augmented by the provision of diets supplemented with the amino acid glutamine (Gln) or by administration of insulin-like growth factor-I (IGF-I). The goal of this study was to investigate potential synergistic effects of Gln and IGF-I on postresection ileal hyperplasia. Rats underwent 80% small bowel resection (SBR) and then were fed low-Gln or L-Gln-enriched diets and subcutaneously given recombinant human IGF-I or vehicle for 7 days. Gln and IGF-I each significantly enhanced adaptive ileal hyperplasia (DNA content) compared with rats receiving vehicle and low-Gln diet. Ileal DNA content was highest when IGF-I was administered together with Gln supplementation. Combined IGF-I plus Gln synergistically increased ileal weight and protein content. This was associated with higher plasma concentrations of IGF-I and Gln than observed when IGF-I or Gln was given individually. Ileal IGF-I mRNA expression rose nearly twofold during gut adaptation after SBR; this response was augmented with IGF-I administration but was unaltered by Gln feeding. In contrast, dietary Gln, but not IGF-I therapy, prevented a decrease in hepatic IGF-I mRNA induced by SBR. We conclude that parenteral IGF-I and enteral Gln have both individual and synergistic effects on ileal adaptation after massive small intestinal resection. These findings support the concept that specific gut-trophic nutrients and growth factors may be combined to enhance intestinal adaptation and possibly reduce the severity of short bowel syndrome after intestinal resection.

Chronic growth hormone treatment in normal rats reduces post-prandial skeletal muscle plasma membrane GLUT1 content, but not glucose transport or GLUT4 expression and localization.

Whether skeletal muscle glucose transport system is impaired in the basal, post-prandial state during chronic growth hormone treatment is unknown. The current study was designed to determine whether 4 weeks of human growth hormone (hGH) treatment (3.5 mg/kg per day) would impair glucose transport and/or the number of glucose transporters in plasma membrane vesicles isolated from hindlimb skeletal muscle of Sprague-Dawley rats under basal, post-prandial conditions. hGH treatment was shown to have no effect on glucose influx (Vmax or K(m)) determined under equilibrium exchange conditions in isolated plasma membrane vesicles. Plasma membrane glucose transporter number (Ro) measured by cytochalasin B binding was also unchanged by hGH treatment. Consequently, glucose transporter turnover number (Vmax/Ro), a measure of average glucose transporter intrinsic activity, was similar in hGH-treated and control rats. hGH did not change GLUT4 protein content in whole muscle or in the plasma membrane, and muscle content of GLUT4 mRNA also was unchanged. In contrast, GLUT1 protein content in the plasma membrane fraction was significantly reduced by hGH treatment. This was associated with a modest, although not significant, decrease in muscle content of GLUT1 mRNA. In conclusion, high-dose hGH treatment for 4 weeks did not alter post-prandial skeletal muscle glucose transport activity. Neither the muscle level nor the intracellular localization of GLUT4 was changed by the hormone treatment. On the contrary, the basal post-prandial level of GLUT1 in the plasma membrane was reduced by hGH. The mRNA data suggest that this reduction might result from a decrease in the synthesis of GLUT1.

ROR gamma: the third member of ROR/RZR orphan receptor subfamily that is highly expressed in skeletal muscle.

In this study, we describe the identification and cloning of a novel member of the nuclear receptor superfamily. This orphan receptor, referred to as ROR gamma, belongs to the ROR/RZR subfamily. The open reading frame of ROR gamma encodes a protein of 560 amino acid residues with a predicted molecular mass of 63 kD. The amino acid sequence of ROR gamma exhibits a 50 and 51% identity with those of ROR alpha/RZR alpha and RZR beta, respectively, whereas the DNA-binding domains were 89% identical. ROR gamma was localized on human chromosome 1. Northern blot analysis using RNA from multiple tissues indicated that ROR gamma is expressed in several tissues but is most highly expressed in skeletal muscle.

Purification, properties, and subcellular localization of foxtail mosaic potexvirus 26-kDa protein.

The open reading frame 2 (ORF2) of the potexviral genome encodes a 24- to 26-kDa protein which is part of the "triple gene block," a group of overlapping ORFs also present in the genomes of the carla-, hordei-, and furoviruses. The product of these ORFs is believed to play a role in the cell-to-cell movement of the viruses in host plants. The amino acid sequences of the homologous ORF2 products encoded by these related viruses suggest that they specify NTP binding and possibly helicase activities. We have used an Escherichia coli expression system to produce significant amounts of the 26-kDa protein (p26) encoded by foxtail mosaic potexvirus ORF2. p28 was purified to near homogeneity by conventional purification methods and some of its biochemical properties were determined. We present evidence that p26 is an ATP, CTP, and RNA binding protein with apparent ATPase activity. Western blot analysis of infected plant extracts using a polyclonal antiserum produced against p26 indicates that it is a relatively stable protein maintained at high levels for at least 6 days following its peak level of expression. Moreover, it is found predominantly in the soluble fraction of infected tissues. An immunocytochemical analysis of infected Chenopodium quinoa leaves reveals that p26 is exclusively associated with cytoplasmic inclusions in proximity to but distinct from aggregates of viral particles.

Two alternatively spliced forms of the human insulin-like growth factor I receptor have distinct biological activities and internalization kinetics.

Two alternatively spliced human insulin-like growth factor I (IGF I) receptor mRNA transcripts have been described that differ by three nucleotides (CAG) starting at position 2829. This results in an amino acid coding sequence change from Thr-Gly to Arg in the extracellular portion of the receptor beta subunit. To investigate the functional significance of this sequence difference, we obtained full-length cDNAs for the CAG+ and CAG- receptor forms, transfected CHO cells, and isolated multiple clones expressing approximately equal numbers of receptors (0.57-0.73 x 10(6) receptors/cell). The two receptors bound IGF I with similar affinity (Kd approximately 1.7 nM), but the CAG- form exhibited an approximately 2-fold increase in IGF I stimulation of receptor autophosphorylation, insulin receptor substrate-1 (IRS-1) tyrosine phosphorylation, thymidine incorporation, and IRS-1-associated phosphatidylinositol 3-kinase activity. In contrast to its higher signaling activity, the rate of receptor-mediated internalization of IGF I by the CAG-receptor was decreased by 50% in comparison with the CAG+ receptor. We conclude that proteins corresponding to the two alternatively spliced human IGF I receptor transcripts are biologically active, but have distinct signaling properties. These experiments further indicate a previously unrecognized role for the extramembranous portion of the beta subunit in receptor signaling and internalization.

New bioactive taxoids from cell cultures of Taxus baccata.

Four new taxoids were isolated from cell cultures of Taxus baccata. Their structures were elucidated by spectroscopic analyses. Two were the aglycones corresponding to previously isolated 7-O-xylosides of taxol C [1] and 10-deacetyltaxol C [2]. The third [3] had an N-methylated side-chain, while the fourth, named taxcultine [4], contained an n-propyl group on the side-chain. All four compounds actively promoted tubulin assembly. Taxol C [1] showed potent and selective cytotoxicity in the NCI human cell line screen.

Clinical and metabolic efficacy of glutamine-supplemented parenteral nutrition after bone marrow transplantation. A randomized, double-blind, controlled study.

OBJECTIVE: To determine whether glutamine-supplemented parenteral nutrition improves nitrogen retention and reduces hospital morbidity compared with standard parenteral nutrition after bone marrow transplantation. DESIGN: Double-blind, randomized, controlled clinical trial. SETTING: University teaching hospital. PATIENTS: Forty-five adults receiving allogeneic bone marrow transplants for hematologic malignancies. INTERVENTION: Parenteral nutrition was initiated the day after bone marrow transplantation (day 1). The experimental solution was supplemented with L-glutamine (0.57 g/kg body weight per day) and provided estimated requirements for energy and protein. The control solution was a standard, glutamine-free, isonitrogenous, isocaloric formula. MEASUREMENTS: Nitrogen balance was determined between days 4 and 11 in the initial 23 patients. The incidence of clinical infection and microbial colonization, time until bone marrow engraftment, indices of clinical care, and other data related to hospital morbidity were recorded for all patients. RESULTS: The glutamine-supplemented patients (n = 24) were clinically similar to the controls (n = 21) at entry. Nutrient intake was similar in both groups; however, nitrogen balance was improved in the glutamine-supplemented patients relative to the controls (-1.4 +/- 0.5 g/d compared with -4.2 +/- 1.2; P = 0.002). Fewer experimental patients developed clinical infection (three compared with nine in the control group; P = 0.041), and the incidence of microbial colonization was also significantly reduced. Hospital stay was shortened in patients receiving glutamine supplementation (29 +/- 1 d compared with 36 +/- 2 d; P = 0.017). CONCLUSION: Patients receiving glutamine-supplemented parenteral nutrition after bone marrow transplantation had improved nitrogen balance, a diminished incidence of clinical infection, lower rates of microbial colonization, and shortened hospital stay compared with patients receiving standard parenteral nutrition. These effects occurred despite no differences between groups in the incidence of fever, antibiotic requirements, or time to neutrophil engraftment.

Glutamine metabolism and its physiologic importance.

The amino acid glutamine has important and unique metabolic functions. It is the most abundant free amino acid in the circulation and in intracellular pools and a precursor for the synthesis of amino acids, proteins, nucleotides, and many other biologically important molecules. It is the most important precursor for ammoniagenesis in the kidney, the major end product of ammonia-trapping pathways in the liver, a substrate for gluconeogenesis, and an oxidative fuel in rapidly proliferating cells and tissues. Glutamine also may have a number of important regulatory roles, increasing protein synthesis and decreasing protein degradation in skeletal muscle and stimulating glycogen synthesis in the liver. The demonstration that glutamine concentrations decrease and tissue glutamine metabolism increases markedly in many catabolic, stressful disease states has led to a reconsideration of the classification of glutamine as a nonessential amino acid and to the alternative hypothesis that glutamine may be a conditionally essential nutrient. This hypothesis has been supported by recent studies that have shown trophic effects of glutamine-supplemented diets on the growth of specific tissues and on total body nitrogen balance. These observations form the basis for current efforts to define the clinical usefulness of glutamine-supplemented nutrition.

Effects of glutamine-enriched parenteral nutrition on the exocrine pancreas.

Total parenteral nutrition (TPN) is associated with intestinal and pancreatic atrophy and pancreatic exocrine insufficiency. Recent investigations have demonstrated that the addition of glutamine to intravenous feedings attenuates TPN-associated intestinal atrophy. However, the effect of glutamine-supplemented intravenous feedings on the pancreas of intact animals is unknown. This study compared the effects of an intravenous infusion of a 2% glutamine-enriched diet (GLN) with an isonitrogenous, isocaloric diet without glutamine (CONT) on the composition and structure of the exocrine pancreas in laboratory rats with and without a 60% small bowel resection. In nonresected, TPN-fed animals, pancreatic weight was significantly increased in the GLN group when compared to CONT (645 +/- 33 g vs 554 +/- 20 g, p less than 0.05). Nonresected GLN animals also had increased pancreatic DNA (3.82 +/- 0.19 mg vs 2.91 +/- 0.49 mg, p less than 0.005) and protein contents (93.0 +/- 5.9 mg vs 76.6 +/- 7.0 mg, p = 0.08) compared to control. Similar significant increases in pancreatic weight, DNA, and protein were observed in intestinally resected animals fed the glutamine diet. When data from CONT and GLN animals were pooled and analyzed together, glutamine significantly increased total pancreatic trypsinogen and lipase contents (p less than 0.05). The increase in trypsinogen in resected GLN animals was significantly greater than in CONT animals (283 +/- 22 vs 139 +/- 23, p less than 0.005). Biochemical and morphometric observations demonstrated that the trophic effects of glutamine on the exocrine pancreas were manifest by acinar hyperplasia and not hypertrophy. Glutamine appears to be an important nutrient for pancreatic exocrine tissue during TPN.(ABSTRACT TRUNCATED AT 250 WORDS)

Glutamine nutrition and requirements.

Glutamine is the most abundant free amino acid in plasma and tissue pools and an important intermediate in a number of metabolic pathways. Glutamine levels decline markedly in the course of many different catabolic disease states and it has recently been suggested that glutamine may be a conditionally essential dietary nutrient rather than a nonessential amino acid. Changes in tissue glutamine concentrations have been shown to correlate with net protein turnover, and there is evidence that glutamine may both stimulate protein synthesis and inhibit protein degradation. In experimental animals, we have shown that the fall in glutamine concentrations in plasma and tissue pools that occurs in the postoperative state can be prevented or reversed by providing large quantities of exogenous glutamine. In gastrointestinal tissues, the provision of glutamine-free total parenteral nutrition solutions is associated with atrophy of mucosal cells and pancreatic exocrine cells. Glutamine-supplemented parenteral formulas result in diminished atrophy of intestinal mucosal and pancreatic exocrine cells; both intravenous and enteral glutamine promote gastrointestinal tissue regeneration following toxic injury. In animals undergoing partial small intestine resection, glutamine feeding leads to increased adaptive hyperplasia in remaining intestinal segments and results in earlier postoperative weight gain. All of these trophic, anabolic effects of glutamine require the administration of quantities that exceed the glutamine content of normal dietary protein. These findings in experimental animals support the hypothesis that glutamine is a conditionally essential nutrient and suggest a potentially important role for glutamine-supplemented nutrition in catabolic disease states.

Glutamine prevents pancreatic atrophy and fatty liver during elemental feeding.

Rats fed an elemental, enteral diet (STD) developed pancreatic atrophy and hepatic steatosis following 60% jejunoileal intestinal resection. An isonitrogenous, isocaloric 2 g/100 ml glutamine-supplemented diet (GLN) significantly attenuated the development of pancreatic atrophy and hepatic steatosis associated with elemental feeding. Pancreatic weight, DNA, and protein were 27, 22, and 40% increased, respectively, in GLN animals. The pancreata of all animals appeared normal by light and electron microscopic examination. GLN animals had 12% less total liver wet weight, 3% less hepatic water content, and 47% less hepatic fat relative to STD rats. Histologic examination of the liver revealed extensive centrilobular fatty vacuolization in STD animals whereas GLN rats had normal looking hepatic parenchyma. Glutamine should be viewed as an important nutrient in elemental diets with trophic effects on the pancreas and protective effects against the development of hepatic steatosis.

Hypothermic anesthesia attenuates postoperative proteolysis.

The catabolic response that commonly occurs after major operation is characterized by net skeletal muscle proteolysis and accelerated nitrogen excretion. This response was absent in patients undergoing cardiac surgical procedures associated with the combination of cardiopulmonary bypass, narcotic anesthesia, neuromuscular blockade, and hypothermia. Forearm nitrogen release was 422 +/- 492 nmol/100 ml X min on the first postoperative day, approximately 25% of preoperative values (1677 +/- 411, p less than 0.05). Nitrogen excretion and the degree of negative nitrogen balance were comparable to levels observed in nonstressed, fasting subjects. The potential role of hypothermia, high-dose fentanyl anesthesia, and neuromuscular blockade in modifying the catabolic response to laparotomy and retroperitoneal dissection was further evaluated in animal studies. Six hours after operation, amino acid nitrogen release from the hindquarter was 84% less than control values (p less than 0.05). Nitrogen excretion and urea production were also reduced compared to normothermic controls. It is concluded that the combination of hypothermia, narcotic anesthesia, and neuromuscular blockade attenuates the catabolic response to injury and thus may be useful in the care of critically ill surgical patients.