Factors influencing elevated serum apolipoprotein B48 in diabetic and control participants.

Factors influencing the concentration of apolipoprotein B48 (apo B48) at fasting and post-prandial time frames are still being elucidated. This study assesses some possible contributing factors including the presence of type 2 diabetes and gender using an established enzyme-linked immunosorbent assay (ELISA) method. Apo B48 and triglyceride (TG) levels were measured before and for two, four and six hours post-prandially in 49 poorly controlled participants with type 2 diabetes and in 60 apparently healthy participants (controls). Apo B48 levels in the control participants increased post-prandially, peaking at four hours (14.81 ± 7.72 µg/mL) with similar responses demonstrated in TG concentrations. Post-prandial apo B48 levels were significantly higher in male control participants as demonstrated by apo B48 area under the curve (AUC); similar responses were also confirmed in triglyceride AUC. Post-prandial apo B48 concentrations in control participants correlated with HOMA-IR (P < 0.05). Apo B48 continued to increase throughout the six hours in participants with type 2 diabetes (17.73 ± 13.46 µg/mL), when levels were significantly greater than in the control participants (13.04 ± 7.67 µg/mL) (P < 0.05) despite a decrease in accompanying TG levels in participants with type 2 diabetes. Using an ELISA method, this study demonstrated that gender, insulin resistance (as evidenced by HOMA-IR) and diabetes status influence serum apo B48 levels. These effects were only apparent post-prandially.

Leucocytosis in women with polycystic ovary syndrome (PCOS) is incompletely explained by obesity and insulin resistance.

OBJECTIVES: Low-grade chronic inflammation predicts cardiovascular outcomes and is observed in women with polycystic ovary syndrome (PCOS). Whether this is entirely a cause or consequence of insulin resistance (IR) is unknown. METHODS: Seventy pairs of women with and without PCOS, matched for age, body mass index (BMI) and IR (HOMA, QUICKI and Avignon index), were generated from a larger cohort of 103 women with and 104 BMI-matched women without PCOS. Women with PCOS were studied in the follicular phase of the menstrual cycle. White cell count (WCC), high-sensitivity CRP (hsCRP) and a series of 12 cytokines and growth factors were measured. These inflammatory markers were also compared between women with PCOS and 10 normal women studied in the follicular, peri-ovulatory and luteal stages. RESULTS: When all subjects were compared, WCC (6.75 × 10(9) vs 5.60 × 10(9 ) g/l, P < 0.005), hsCRP (4.04 vs 2.90 mg/l, P < 0.05) and IL-6 (1.11 vs 0.72 pg/ml, P < 0.05) were greater in women with PCOS. Pair-matching for IR eliminated between-group differences in hsCRP and cytokines but did not alter the difference in WCC (6.60 × 10(9) vs 5.60 × 10(9 ) g/l, P < 0.005). WCC was greater in PCOS compared to normal women at all stages of the menstrual cycle. CONCLUSIONS: Low-grade inflammation occurs in PCOS. Increased hsCRP and cytokines are associated with IR, but increased WCC is observed even when IR is accounted for. The explanation for this and its clinical significance is unknown.

Serum prolactin concentration at presentation of non-functioning pituitary macroadenomas.

OBJECTIVE: Serum PRL levels at presentation may be useful in distinguishing between disconnection hyperprolactinemia in non-secretory pituitary adenomas and prolactinomas in order to guide appropriate therapy; however, there is a debate regarding the discriminatory PRL thresholds. We aimed to examine PRL concentrations at presentation in a cohort of histologically proven non-functioning pituitary adenomas (NFPA). DESIGN AND METHODS: Retrospective case note analysis was performed. Clinical, biochemical, histopathological and radiological data were recorded and analyzed. Complete data were available for 250 subjects with NFPA. RESULTS: Of the study population, 44.8% were hyperprolactinemic at presentation, 55.3% of whom were female. Of those with hyperprolactinemia, 73.2% had PRL<1000 mIU/l on presentation, 24.1% had PRL between 1000 and 1999 mIU/l. Only 2.7% (no.=3 females, 1.2% whole cohort) had PRL>2000 mIU/l (94.3 ng/ml), 2 of whom were pregnant. No male subject and no subjects with an intrasellar macroadenoma had serum PRL>1000 mIU/l (47.2 ng/ml). Overall, serum PRL was not higher among 43 subjects taking medications known to raise PRL. CONCLUSIONS: Our data support recent evidence that the serum PRL concentration is rarely >1000 mIU/l in males, or >2000 mIU/l in females, with non-functioning macroadenomas and that, once other contributing factors to the hyperprolactinemia have been excluded, a trial of dopamine agonist therapy for such lesions is indicated.

Well-known but rare pathogen in neonates: Listeria monocytogenes.

Listeria monocytogenes is a very important life-threatening bacteria in certain risk groups such as neonates, pregnant women, elderly people, transplant recipients and others with impaired cell-mediated immunity. However, its infections are very rare in healthy children. Reports of listeriosis in newborn period are limited. We report a case of neonatal listeriosis with erythematous rash, intractable convulsions, severe early neonatal sepsis, disseminated intravascular coagulation, multiple organ dysfunction syndrome and death. Although an empirical antibiotic therapy including ampicillin (semisentetic penicillin) and aminoglycoside combination is effective by the means of a probable Listeria infection, the progression of the very early-onset disease may be fatal, despite vigorous treatment efforts as in our case.

Acute diabetic neuropathy following improved glycaemic control: a case series and review.

SUMMARY: We present three cases of acute diabetic neuropathy and highlight a potentially underappreciated link between tightening of glycaemic control and acute neuropathies in patients with diabetes. Case 1: A 56-year-old male with poorly controlled type 2 diabetes (T2DM) was commenced on basal-bolus insulin. He presented 6 weeks later with a diffuse painful sensory neuropathy and postural hypotension. He was diagnosed with treatment-induced neuropathy (TIN, insulin neuritis) and obtained symptomatic relief from pregabalin. Case 2: A 67-year-old male with T2DM and chronic hyperglycaemia presented with left lower limb pain, weakness and weight loss shortly after achieving target glycaemia with oral anti-hyperglycaemics. Neurological examination and neuro-electrophysiological studies suggested diabetic lumbosacral radiculo-plexus neuropathy (DLPRN, diabetic amyotrophy). Pain and weakness resolved over time. Case 3: A 58-year-old male was admitted with blurred vision diplopia and complete ptosis of the right eye, with intact pupillary reflexes, shortly after intensification of glucose-lowering treatment with an SGLT2 inhibitor as adjunct to metformin. He was diagnosed with a pupil-sparing third nerve palsy secondary to diabetic mononeuritis which improved over time. While all three acute neuropathies have been previously well described, all are rare and require a high index of clinical suspicion as they are essentially a diagnosis of exclusion. Interestingly, all three of our cases are linked by the development of acute neuropathy following a significant improvement in glycaemic control. This phenomenon is well described in TIN, but not previously highlighted in other acute neuropathies. LEARNING POINTS: A link between acute tightening of glycaemic control and acute neuropathies has not been well described in literature. Clinicians caring for patients with diabetes who develop otherwise unexplained neurologic symptoms following a tightening of glycaemic control should consider the possibility of an acute diabetic neuropathy. Early recognition of these neuropathies can obviate the need for detailed and expensive investigations and allow for early institution of appropriate pain-relieving medications.

A new primate from the Middle Eocene of Myanmar and the Asian early origin of anthropoids.

A new genus and species of anthropoid primate, Bahinia pondaungensis gen. et sp. nov., is described from the Yashe Kyitchaung locality in the Late Middle Eocene Pondaung Formation (Myanmar). It is related to Eosimias, but it is represented by more complete remains, including upper dentition with associated lower jaw fragment. It is interpreted as a new representative of the family Eosimiidae, which corresponds to the sister group of the Amphipithecidae and of all other anthropoids. Eosimiidae are now recorded from three distinct Middle Eocene localities in Asia, giving support to the hypothesis of an Asian origin of anthropoids.

How many sputum samples should be examined during follow-up of tuberculosis patients in Myanmar: two or one?

Setting: Ten selected microscopy centres in Sagaing Region, Myanmar, functioning under an external quality assurance system with no reported major errors. Objective: To assess the pattern of serial sputum results (NN, both smear-negative; NP, first smear-negative and second smear-positive; PN, first smear-positive and second smear-negative; and PP, both smear-positive) among follow-up sputum microscopy examinations of tuberculosis (TB) patients (end of intensive phase, mid-continuation phase and end of treatment) conducted from 1 November 2017 to 15 April 2018. Design: Cross-sectional study using secondary data (laboratory registers). Results: Of 2001 examinations, 94 (4.7%) were smear-positive: 66 PP (3.3%), 12 PN (0.6%) and 16 NP (0.8%); 75% of NP results were scanty. The proportion of NP results was 0.8% (95%CI 0.5-1.3), i.e., 125 smears (95%CI 77-200) were required to detect one additional smear-positive result in the second sample. Of the 16 NP results (15 patients), 14 were tested using Xpert® MTB/RIF and none had rifampicin resistance. During the continuation phase of treatment, 13 became smear-negative, one remained smear-positive and one had unknown follow-up smear status. Conclusion: The benefit of the second sputum sample for monitoring anti-tuberculosis treatment was negligible. Given the favourable resource implications (reduced laboratory workload and costs), we recommend changing the policy from two sputum smears to one during follow-up sputum examinations of TB patients.

Contexte : Dix centres de microscopie sélectionnés de la région de Sagaing, Myanmar, fonctionnant avec un système d'assurance de qualité externe sans erreurs majeures rapportées.Objectif : Evaluer les profils de séries de résultats de crachats (NN, deux frottis négatifs ; NP, premier frottis négatif et deuxième frottis positif ; PN, premier frottis positif et deuxième frottis négatif ; et PP, deux frottis positifs) parmi les examens de suivi de microscopie de crachats de patients TB (à la fin de la phase intensive, au milieu de la phase de continuation et à la fin du traitement) réalisés du 1e novembre 2017 au 15 avril 2018.Schéma : Etude transversale grâce à des données secondaires (registres de laboratoire).Résultats : Sur 2001 examens, 94 (4,7%) ont eu un frottis positif : 66 (3,3%) PP ; 12 (0,6%) PN ; 16 (0,8%) NP ; 75% des NP avaient de rares bacilles. La proportion de NP a été de 0,8% (IC95% 0,5­1,3), impliquant qu'il a fallu 125 frottis (IC95% 77­200) pour détecter un frottis positif supplémentaire dans un deuxième échantillon. Sur les 16 NP (15 patients), 14 ont été testés par Xpert® MTB/RIF et aucun n'a eu de résistance à la rifampicine. Lors de la continuation du traitement, 13 sont devenus à frottis négatif, un patient est resté à frottis positif et un autre a eu un frottis de suivi « indéterminé ¼.Conclusion : Le bénéfice du deuxième échantillon de crachats pour le suivi du traitement antituberculeux a été négligeable. Devant les implications favorables en termes de ressources (charge de travail et coûts réduits pour le laboratoire), nous recommandons de modifier la politique de deux frottis de crachats à un seul lors du suivi de patients TB par examens des crachats.

Marco de Referencia: Diez centros de microscopia escogidos en la región de Sagaing de Birmania, que funcionan con un sistema externo de garantía de la calidad y no notifican errores importantes.Objetivos: Evaluar el perfil de los resultados seriados del esputo (NN, ambas baciloscopias negativas; NP, primera baciloscopia negativa y segunda positiva; PN, primera baciloscopia positiva y segunda negativa; y PP, ambas baciloscopias positivas) en las baciloscopias de esputo de seguimiento de los pacientes con tuberculosis (TB) (al final de la fase intensiva, en medio de la fase de continuación y al final del tratamiento), realizadas del 1° de noviembre del 2017 al 15 de abril del 2018.Métodom: Fue este un estudio transversal que utilizó datos secundarios (los registros de laboratorio).Resultados: De las 2001 baciloscopias realizadas, 94 (4,7%) fueron positivas, a saber: 66 (3,3%) PP; 12 (0,6%) PN; 16 (0,8%) NP; 75% de los resultados NP se notificaron como 'escasos bacilos'. La proporción de resultados NP fue 0,8% (IC95% 0,5­1,3), lo cual indica que se precisaron 125 baciloscopias a fin de detectar una baciloscopia positiva adicional en la segunda muestra (IC95% 77­200). De los 16 casos NP (15 pacientes), 14 se examinaron mediante la prueba Xpert® MTB/RIF y ninguno exhibió resistencia a rifampicina. Durante la fase de continuación del tratamiento, en 13 casos la baciloscopia se hizo negativa, uno permaneció positivo y en otro caso el resultado de la baciloscopia de seguimiento era 'desconocido'.Conclusión: La utilidad de una segunda muestra de esputo en la supervisión del tratamiento antituberculoso fue insignificante. Teniendo en cuenta sus repercusiones económicas favorables (disminución de la carga de trabajo y los costos de laboratorio), se recomienda cambiar la norma de practicar dos muestras de esputo por una sola muestra, durante las baciloscopias de seguimiento de los pacientes con TB.

Physical interaction between a novel domain of the receptor Notch and the transcription factor RBP-J kappa/Su(H).

BACKGROUND: The mammalian transcription factor RBP-J kappa binds to the DNA sequence motif CGTGGGAA and is involved in the regulation of gene expression; for example, it plays a part in the transactivation of viral and cellular genes by Epstein-Barr virus nuclear antigen-2. The Drosophila homologue of RBP-J kappa is the product of the Suppressor of Hairless (Su(H)) gene. Su(H) is a neurogenic gene that acts downstream of Notch, which encodes a cell-surface receptor. Furthermore, in the mouse, the phenotypes of homozygous mutant Notch1 embryos are very similar to those of homozygous mutant RBP-J kappa embryos. Recent studies, using the yeast two-hybrid system, have led to the suggestion that the CDC10/ankyrin-like repeats of the Drosophila Notch protein interact with the Su(H) protein. RESULTS: We searched for proteins that interact with mouse RBP-J kappa using the yeast two-hybrid system, and in this way identified a short intracellular region (mRAM23) of the mouse Notch1 protein that lacks any known sequence motif. In vitro interaction studies, using proteins fused to glutathione-S-transferase, showed that RBP-J kappa and Su(H) bind directly to the RAM23 regions of mouse Notch1 and Drosophila Notch, respectively. Immunoprecipitation analysis showed that RBP-J kappa and the mRAM23 region of mouse Notch1 also interact in vivo. Further studies, including site-directed mutagenesis experiments, narrowed down the region of mouse Notch1 that interacts with RBP-J kappa. The results indicate that this region is less than 50 amino-acid residues in length, and lies immediately downstream of the transmembrane region. CONCLUSIONS: We show that the transcription factor RBP-J kappa/Su(H) interacts directly with a novel intracellular domain of the cell-surface receptor Notch. RBP-J kappa/Su(H) does not appear to interact with Notch via the CDC10/ankyrin repeats implicated in previous studies.

Efficient transmicrocatheter delivery of functional fibroblasts with a bioengineered collagen gel-platinum microcoil complex: toward the development of endovascular cell therapy for cerebral aneurysms.

BACKGROUND AND PURPOSE: Endoaneurysmal implantation of fibroblasts may promote healing of aneurysms and reduce recanalization after therapeutic embolization. The purpose of our study was to develop a device for delivery of fibroblasts with use of current microcoil technology. MATERIALS AND METHODS: Cell carrier devices and cell-free devices were fabricated by associating collagen gels (with or without fibroblasts) with platinum microcoils. During the propagation of control cell carrier devices for 1 week in culture, cell-mediated gel contraction (CMGC) occurred. Modified cell carrier devices created by glutaraldehyde cross-linking, ascorbate coculture, or extended CMGC were also characterized in vitro. Devices were deployed through microcatheters (533 microm lumen, 160 cm length). Gel retention, cell retention, cell death, and the ability to support local cell migration were analyzed in vitro. RESULTS: Cell viability was reduced by glutaraldehyde cross-linking but not by microcatheter transit. During microcatheter transit, cell carrier devices liberated minimal particulate matter and cellular DNA. Liberated particulate matter was reduced by glutaraldehyde cross-linking (P < .05) and extended CMGC (P < .04). Only cell carrier devices treated with glutaraldehyde cross-linking did not exhibit cell migration after microcatheter transit. Passage of cell-free devices through microcatheters sheared off most of their collagen gel. CONCLUSION: Collagen gel-platinum microcoil complexes can mediate efficient transmicrocatheter delivery of viable, migration-capable fibroblasts. CMGC is a necessary component of the process of gel stabilization that enables successful microcatheter transit. Although extended CMGC and glutaraldehyde cross-linking enhance gel stabilization, glutaraldehyde cross-linking decreases cell viability and migratory potential.

LIM protein KyoT2 negatively regulates transcription by association with the RBP-J DNA-binding protein.

The RBP-J/Su(H) DNA-binding protein plays a key role in transcriptional regulation by targeting Epstein-Barr virus nuclear antigen 2 (EBNA2) and the intracellular portions of Notch receptors to specific promoters. Using the yeast two-hybrid system, we isolated a LIM-only protein, KyoT, which physically interacts with RBP-J. Differential splicing gave rise to two transcripts of the KyoT gene, KyoT1 and KyoT2, that encoded proteins with four and two LIM domains, respectively. With differential splicing resulting in deletion of an exon, KyoT2 lacked two LIM domains from the C terminus and had a frameshift in the last exon, creating the RBP-J-binding region in the C terminus. KyoT1 had a negligible level of interaction with RBP-J. Strong expression of KyoT mRNAs was detected in skeletal muscle and lung, with a predominance of KyoT1 mRNA. When expressed in F9 embryonal carcinoma cells, KyoT1 and KyoT2 were localized in the cytoplasm and the nucleus, respectively. The binding site of KyoT2 on RBP-J overlaps those of EBNA2 and Notchl but is distinct from that of Hairless, the negative regulator of RBP-J-mediated transcription in Drosophila. KyoT2 but not KyoT1 repressed the RBP-J-mediated transcriptional activation by EBNA2 and Notch1 by competing with them for binding to RBP-J and by dislocating RBP-J from DNA. KyoT2 is a novel negative regulatory molecule for RBP-J-mediated transcription in mammalian systems.

Dyspnea differentiation index: A new method for the rapid separation of cardiac vs pulmonary dyspnea.

STUDY OBJECTIVE: To assess the utility of a new parameter in the differentiation of dyspnea of cardiac origin from dyspnea of pulmonary origin. METHODS: The peak expiratory flow (PEF) rate and the partial pressure of oxygen in arterial blood (PaO(2)) were measured in 71 patients with the chief complaint of dyspnea. The patients were treated in the hospital, and the final diagnosis (cardiac or pulmonary) of the cause of dyspnea was made at discharge. We defined a new measure, the dyspnea differentiation index (DDI), as (PEF x PaO(2))/1,000. We performed a receiver operating characteristic (ROC) curve analysis of the data to define the measure that best distinguished cardiac from pulmonary dyspnea. The curves also allowed us to establish an optimal cut-off point to distinguish between cardiac and pulmonary dyspnea. RESULTS: Patients with pulmonary dyspnea had a significantly lower mean PEF than patients with cardiac dyspnea (144 +/- 66 vs 267 +/- 97 L/min, respectively; p < 0.001). They also had a lower DDI than patients with cardiac dyspnea (8.4 +/- 4.0 vs 18.4 +/- 7.9 L-mm/min, respectively; p < 0.001). These two measures, PEF and DDI, also best distinguished pulmonary from cardiac dyspnea. PEF was able to diagnose the correct cause of dyspnea in 72% of patients, and DDI was correct in 79% of patients. This compares favorably to the performance of the emergency department physicians, who were able to predict the correct diagnosis in only 69% of patients. CONCLUSION: These results demonstrate that the PEF by itself is useful in differentiating between cardiac and pulmonary causes of dyspnea, but that the calculation of DDI is superior in this regard.

Prolonged effect of troglitazone (CS-045) on xenograft survival of hybrid artificial pancreas.

Troglitazone (CS-045), a thiazolidinedione derivative, is a new oral antidiabetic agent that enhances insulin sensitivity and improves insulin responsiveness. In this study we examined the effects of CS-045 on the survival of xenografted bioartificial pancreas. Isolated rat islets were microencapsulated with three-layer agarose microcapsules (polybrene, carboxymethyl cellulose, and an agarose-polystyrene sulfonic acid mixture). Diabetes was induced by intraperitoneal injection of streptozotocin 220 mg/kg. Recipient diabetic mice were separated into two groups. In the CS-045 treated group, the recipient mice were given feed mixed with CS-045 (0.2% w/w) starting from 1 wk before transplantation up to graft failure. The mice in the control group had feed without CS-045. Three hundred microencapsulated rat islets were xenotransplanted into the intraperitoneal cavity of each recipient mouse in both groups. One month after xenotransplantation, IVGTT was performed for all recipients. Xenotransplantation of 300 rat islets in microcapsules decreased the nonfasting blood glucose levels of both groups within 2 days. In the CS-045-treated group (n = 3), the normoglycemic period lasted for more than 1 mo without administration of immunosuppressive drugs (45 +/- 4.3 days). However, in the control group (n = 4), the blood glucose levels of all recipients were already elevated on day 4. In the IVGTT study, the glucose assimilation was markedly and significantly better in the CS-045-treated group than in the control group (K = 1.7 +/- 0.1 vs. 0.7 +/- 0.28 respectively, p < 0.01). This study demonstrates that a newly developed oral antidiabetic agent, CS-045 could favorably ameliorate the diabetic state of the recipients xenotransplanted with the bioartificial pancreas, leading to an improved glucose tolerance and longer xenograft survival.

A newly developed three-layer agarose microcapsule for a promising biohybrid artificial pancreas: rat to mouse xenotransplantation.

We examined the effectiveness of an improved version of a three-layer agarose microcapsule in islet xenotransplantation. The microcapsule is composed of a mixture of 5% agarose and 5% polystyrene sulfonic acid. The other two outer layers are polybrene and carboxymethyl cellulose. The agarose/polystyrene sulfonic acid membrane is for the purpose of immunoisolation, suppression of complement activity and reinforcement of the microcapsule. The polybrene layer suppresses the polystyrene sulfonic acid leakage by forming a polyionic complex at the surface of the agarose/polystyrene sulfonic acid membrane. The outermost layer, a carboxymethyl cellulose coating, improves the biocompatibility of the microcapsule. In vitro static incubation study showed that the insulin secretion from rat islets in microcapsules in response to 16.7 mM glucose stimulation was more than four times higher than that on 3.3 mM glucose stimulation (n = 8). In an in vivo study, 500 rat islets in microcapsules were xenogenically implanted in the abdominal cavity of mice with streptozotocin-induced diabetes. The graft survival times ranged from 2 to 5 mo, the average being 75 days (n = 5). Our results demonstrate that the improved version of the three-layer agarose microcapsule can effectively prolong the xenograft survival time without employing immunosuppressants, suggesting that this microcapsule could provide a promising biohybrid artificial pancreas for future clinical applications.

Improved large-scale isolation of breeder porcine islets: possibility of harvesting from nonheart-beating donor.

To establish a large-scale isolation procedure for adult porcine islets usable as a donor source for xenotransplantation and as a model of human islet isolation, we improved several characteristics of the conventional isolation procedure. At a slaughterhouse we first selected a breeder pig over 1.5 years old (and over 200 kg in weight) with warm ischemic time (WIT) of 15 +/- 2 minutes as nonheart-beating donors. Then, we made a special enzymic mixture that consisted of collagenase S-1 (260 U/mg, NittaZelatin, Japan), collagenase P (1.86 U/ml Lyo Boehringer-Mannheim, USA), DNase (Sigma, St. Louis, Mo), Disparse (NittaZelatin, Japan), and protease inhibitor (Sigma). Third, this mixture was injected very gently into the pancreatic duct at the time of pancreatic harvesting. To prevent overdigestion of the pancreas, the mixture was first cooled to less than 10 degrees C. Fourth, during the warm digestion of pancreas, the pancreas with the enzymic mixture was quietly put in a water bath at 37 degrees C without mechanical shaking. Fifth, we purified the islets with a COBE 2991 cell processor by the Dextran 70 gradient method, because Dextran 70 is very cheap and has the same purification effect as the Ficoll gradient. The results of 10 consecutive breeder porcine islet isolations are reported. The total yield of isolations of islets over 50 microm in the longest diameter after staining with Dithizone (DTZ) was 85,900 +/- 19,954 islets, 291,667 +/- 240,452 IEQ (2,900 +/- 2,324 IEQ/g). The purity of the isolated islets was very high: 90.2 +/- 3.8%. Glucose stimulation during in vitro incubation induced significant insulin release from isolated breeder porcine islets. In two of the diabetic rats receiving encapsulated islets grafts using a mesh-reinforced polyvinyl alcohol hydrogel bag (MRPB), a prominent reduction in serum glucose levels (less than 200 mg/dL) persisted for 13 and 19 days, respectively, after intraperitoneal xenotransplantation islets without immunosuppression. In conclusion, we succeeded in a more efficient and less-expensive isolation of a large amount of adult porcine islets from a nonheart-beating donor.

Application of a novel B cell line MIN6 to a mesh-reinforced polyvinyl alcohol hydrogel tube and three-layer agarose microcapsules: an in vitro study.

This study examines the function of a novel B cell line (MIN6) enclosed in hybrid bioartificial pancreas with mesh-reinforced polyvinyl alcohol hydrogel tube (MRPT) or with improved, three-layer agarose microcapsules. MIN6 was established from insulinomas obtained by targeted expression of the simian virus 40 T-antigen gene in transgenic mice. MIN6 retains the ability to secrete insulin in response to physiological glucose concentrations. The MRPT and the three-layer agarose microcapsules, which were developed to act as an artificial pancreas, were readily permeated by insulin, glucose, and other nutrients. Both can immunoisolate enclosed MIN6 cells from the recipient's humoral and cellular immunosystems, which causes a xenogeneic rejection response. MIN6 cells (5.0 x 10(6) or 1.5 x 10(6)) were enclosed in MRPT or in a hundred three-layer microcapsules and subjected to an in vitro perifusion study or a static incubation study to observe the insulin release from each bioartificial pancreas in response to glucose stimulation. In vitro study revealed that the insulin secretion in response to 16.7 mM glucose stimulation was twice that with 3.3 mM glucose stimulation with both MRPT and the three-layer agarose microcapsules. The present study demonstrates that MIN6 effectively functions as a bioreactor for the hybrid bioartificial pancreas. The application of MIN6 cells to the hybrid bioartificial pancreas may offer a solution to the current serious dearth of organs.

Effects of endothelin on microcirculation of the pancreas.

Endothelin, a newly described endothelial-derived peptide, has potent vasoconstrictive properties and has been speculated to play a physiological role in the regulation of blood flow in some organs. The present study was designed to evaluate the effects of endothelin-1, endothelin-2 and endothelin-3 on the pancreatic microcirculation. Pancreatic tissue blood flow was measured by a laser Doppler flow meter in anesthetized dogs and endothelin-1, endothelin-2 or endothelin-3 was injected intravenously in graduated doses. Endothelins induced dose-dependent decreases in pancreatic tissue blood flow. Endothelin-1, endothelin-2 and endothelin-3 at a dose of 100 pmol/kg reduced pancreatic blood flow by 45.4%, 19.6% and 51.9%, respectively, whereas systemic arterial blood pressure was not significantly affected. When endothelin-3 was administered at a dose of 1000 pmol/kg, pancreatic blood flow was decreased by 73.5% with a concomitant increase of systemic arterial blood pressure by 17.6%. Endothelins potently decreased pancreatic tissue blood flow, suggesting a possible role of these agents in regulating the pancreatic microcirculation.

New type of matrix support for bone marrow cell cultures: in vitro culture and in vivo transplantation experiments.

A new type of bone marrow cell culture system was developed by using a highly porous substrate matrix, i.e., porous polyvinyl formal (PVF) resin. Murine bone marrow (BM) cells were cultured without the use of exogenous growth factors in a three-dimensional matrix support made of collagen coated porous PVF resin. To examine the optimal conditions for highest stromal cell density, short-term and long-term in vitro culture experiments using PVF were performed. In the short-term culture experiments, it was found that cubes of PVF (10 x 10 x 2 mm and 130 microm in pore size) coated with type I collagen with a seeding density of 2x10(7) BM cells offered the most appropriate culture conditions. In the long-term cultures, BM cells in PVF maintained their viability for up to 6 weeks. In another series of re-inoculation experiments, freshly isolated BM cells were inoculated onto the already developed stromal layer. In this study, a higher cell density of the stromal layer was obtained in the PVF culture compared with those in the control dish culture. Based upon the results of in vitro experiments, in vivo transplantation studies were also performed. Histologic examinations of the subcutaneously transplanted PVF with stroma revealed host derived hematopoiesis inside the PVF matrix. Moreover, survival of approximately 15% of the transplanted BM cells that were cultured in PVF were confirmed in X-ray irradiated recipients. From these results, it is suggested that PVF resin is a promising three-dimensional substrate for BM cell culture and that it can maintain hematopoietic stem cells or progenitor cells after transplantation.

Mechanisms of hearing loss in acoustic neuroma: an otoacoustic emission study.

Evoked otoacoustic emissions (EOAE) are active mechanical responses from the cochlea which provide information about the integrity of the preneural cochlear receptor mechanisms. It may be hypothesised, therefore, that if a hearing impairment is neural in origin, normal EOAEs may be obtained from the cochlea, which, although dissociated, is functioning normally. This study examined the status of the cochlea with EOAE in patients with cochlear (Meniere's disease) and neural (surgically proven acoustic neuroma) disease. In patients with presumed cochlear lesions, no emissions were present with mean hearing worse than 40 dB across a frequency range of 0.5 to 4 kHz. Similarly, an EOAE was not present in any of the 26 acoustic neuroma patients studied when the average (0.5 to 4 kHz) hearing was greater than 40 dB. We conclude that dissociation of the cochlea in patients with acoustic neuroma appears to be rare and, in fact, cochlear involvement occurs in most cases. Possible mechanisms responsible for the effect on the cochlea in this group include degenerative changes due to chronic partial obstruction of the blood supply by the tumour, biochemical alterations in the inner ear fluids, loss of efferent control of active mechanical tuning, and hair cell degeneration secondary to neuronal loss in the eighth nerve.

An unusual case of laryngeal carcinoma.

A 62-year-old male patient presented with carcinoma of the larynx which behaved in an atypical fashion clinically. It increased in size rapidly within a period of 5 weeks and clinically presented as a dumbell-shaped neck swelling over the thyroid alae. It had features on plain x-ray, tomography and CT scan which led to the diagnosis of chondrosarcoma of the larynx. After total laryngectomy, it turned out to be a squamous cell carcinoma of the larynx with some unusual histopathological features including bone formation in the tumour.

Barriers to exercise in obese patients with type 2 diabetes.

BACKGROUND: Although regular exercise is a critical component of the management of type 2 diabetes, many patients do not meet their exercise targets. Lack of exercise is associated with obesity and adverse cardiovascular outcomes. AIM: We aimed to assess exercise habits in obese Irish patients with type 2 diabetes to determine if patients are adhering to exercise guidelines and to identify perceived barriers to exercise in this group. DESIGN: A cross-sectional study of obese patients with type 2 diabetes attending routine outpatient diabetes clinics at our institution, a public teaching hospital located on the outskirts of Dublin City. METHODS: A total of 145 obese patients with type 2 diabetes were administered a questionnaire to evaluate exercise habits and perceived barriers to exercise. Anthropometric details were measured. RESULTS: About 47.6% (n = 69) of patients exercised for <150 minutes per week (40% of males, 62% of females; P = 0.019) and these patients had a higher body mass index than those meeting targets (35 vs. 33.5 kg/m(2); P = 0.02). Perceived barriers to exercise were varied, with lack of time and physical discomfort being the most common. Reported barriers to exercise varied with age, gender and marital status. CONCLUSION: This study highlights the challenges facing clinicians in improving exercise levels in patients, and the need to identify the specific barriers to exercise in the individual to improve health outcomes.