bluuebunny/crossref_metadata_2025 huggingface dataset:
Sevoflurane Depresses Glutamatergic Neurotransmission to Brainstem Inspiratory Premotor Neurons but Not Postsynaptic Receptor Function in a Decerebrate Dog Model
Authors: Stucke Astrid G. , Zuperku Edward J. , Tonkovic-Capin Viseslav , Krolo Mirko , Hopp Francis A. , Kampine John P. , Stuth Eckehard A. E.
Published: June 2005

Background

Inspiratory bulbospinal neurons in the caudal ventral medulla are premotor neurons that drive motoneurons, which innervate pump muscles such as the diaphragm and external intercostals. Excitatory drive to these neurons is mediated by N-methyl-d-aspartate (NMDA) receptors and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors and is modulated by an inhibitory gamma-aminobutyric acid type A (GABAA)ergic input. The authors investigated the effect of sevoflurane on these synaptic mechanisms in decerebrate dogs.

Methods

Studies were performed in decerebrate, vagotomized, paralyzed, and mechanically ventilated dogs during hypercapnic hyperoxia. The effect of 1 minimum alveolar concentration sevoflurane on extracellularly recorded activity of single neurons was measured during localized picoejection of the GABAA receptor blocker bicuculline and the glutamate agonists AMPA and NMDA. Complete blockade of the GABAAergic mechanism by bicuculline allowed differentiation between the effects of sevoflurane on overall GABAAergic inhibition and on overall glutamatergic excitation. The neuronal responses to exogenous AMPA and NMDA were used to estimate the anesthetic effect on postsynaptic glutamatergic neurotransmission.

Results

One minimum alveolar concentration sevoflurane depressed the spontaneous activity of 23 inspiratory premotor neurons by (mean +/- SD) 30.0 +/- 21.0% (P < 0.001). Overall glutamatergic excitation was depressed 19.2 +/- 18.5% (P < 0.001), whereas overall GABAAergic inhibition was enhanced by 11.9 +/- 25.1% (P < 0.05). The postsynaptic responses to exogenous AMPA and NMDA did not change.

Conclusion

One minimum alveolar concentration depressed the activity of inspiratory premotor neurons by a reduction of glutamatergic excitation and an increase in overall inhibition. The postsynaptic AMPA and NMDA receptor response was unchanged. These findings contrast with studies in inspiratory premotor neurons where halothane did not change overall inhibition but significantly reduced the postsynaptic glutamate receptor response.
Sevoflurane Enhances γ-Aminobutyric Acid Type A Receptor Function and Overall Inhibition of Inspiratory Premotor Neurons in a Decerebrate Dog Model
Authors: Stucke Astrid G. , Zuperku Edward J. , Krolo Mirko , Brandes Ivo F. , Hopp Francis A. , Kampine John P. , Stuth Eckehard A. E.
Published: June 2005

Background

Inspiratory premotor neurons in the caudal ventral medulla relay excitatory drive to phrenic and inspiratory intercostal motoneurons in the spinal cord. These neurons are subject to tonic gamma-aminobutyric acid type A (GABAA)ergic inhibition. In a previous study, 1 minimum alveolar concentration (MAC) sevoflurane depressed overall glutamatergic excitatory drive and enhanced overall GABAAergic inhibitory drive to the neurons. This study investigated in further detail the effects of sevoflurane on GABAAergic inhibition by examining postsynaptic GABAA receptor activity in these neurons.

Methods

Studies were performed in decerebrate, vagotomized, paralyzed, and mechanically ventilated dogs during hypercapnic hyperoxia. The effect of 1 MAC sevoflurane on extracellularly recorded neuronal activity was measured during localized picoejection of the GABAA receptor antagonist bicuculline and the GABAA agonist muscimol. Complete blockade of GABAAergic inhibition by bicuculline allowed estimation of the prevailing overall inhibition of the neuron. The neuronal response to muscimol was used to assess the anesthetic effect on the postsynaptic GABAA receptor function.

Results

One MAC sevoflurane depressed the spontaneous activity of 21 inspiratory premotor neurons by (mean +/- SD) 32.6 +/- 20.5% (P < 0.001). Overall excitatory drive was depressed 17.9 +/- 19.8% (P < 0.01). Overall GABAAergic inhibition was enhanced by 18.5 +/- 18.2% (P < 0.001), and the postsynaptic GABAA receptor function was increased by 184.4 +/- 121.8% (n = 20; P < 0.001).

Conclusion

One MAC sevoflurane greatly enhanced GABAA receptor function on inspiratory premotor neurons and increased overall synaptic inhibition but to a smaller extent, indicating that the presynaptic inhibitory input was also reduced. Therefore, the anesthetic depression of spontaneous inspiratory premotor neuronal activity by 1 MAC sevoflurane in vivo is due to a combined effect on the two major ionotropic synaptic neurotransmitter systems with a decrease in overall glutamatergic excitation and a strong enhancement of postsynaptic GABAA receptor function.
Pyruvate Modulates Hepatic Mitochondrial Functions and Reduces Apoptosis Indicators during Hemorrhagic Shock in Rats
Authors: Sharma Pushpa , Walsh Kane T. , Kerr-Knott Kimberly A. , Karaian John E. , Mongan Paul D.
Published: June 2005

Background

Dysfunctional mitochondria have been widely accepted as one of the key targets and a mediator of secondary cell injury and organ failure during hemorrhagic shock (HS). The liver is known to be the first organ to display the signs of injury during HS. This report describes experiments to determine whether modulation of hepatic mitochondrial dysfunctions by pharmacologic agents could prevent liver injury in rats subjected to HS.

Methods

In this study, Sprague-Dawley rats were either treated as controls or subjected to computer-controlled arterial hemorrhage (40 mmHg) for 60 min followed by resuscitation with hypertonic saline, hypertonic beta-hydroxybutyrate, or hypertonic sodium pyruvate for the next 60 min before death. During the course of the experiment, animals were continuously monitored for hemodynamic and metabolic parameters. At the end of the experiment, the liver was excised and examined for oxidative injury, mitochondrial functions, expression of nitric oxide synthase, and indicators of apoptosis.

Results

In comparison to hypertonic saline and hypertonic beta-hydroxybutyrate, pyruvate significantly protected the liver from oxidative injury, prevented the up-regulation of nitric oxide synthase, inhibited pyruvate dehydrogenase deactivation, and improved cellular energy charge and mitochondrial functions. In addition, pyruvate also reduced cleavage of poly-adenosine diphosphate ribose polymerase by preventing leakage of mitochondrial cytochrome c in the liver of HS animals.

Conclusions

These data suggest that modulation of mitochondrial metabolic functions is likely to be one of the important mechanisms by which pyruvate exerts its protective effects on the liver during HS and resuscitation in rats.
A Comparative Study of Sequential Epidural Bolus Technique and Continuous Epidural Infusion
Authors: Ueda Kenichi , Ueda Wasa , Manabe Masanobu
Published: June 2005

Background

In this randomized, double-blind study, the authors compared the effectiveness of a sequential epidural bolus (SEB) technique versus a standard continuous epidural infusion (CEI) technique of local anesthetic delivery. Both techniques used the same hourly dose of local anesthetic.

Methods

Sixteen gynecologic patients undergoing abdominal surgery received postoperative epidural analgesia using 0.75% ropivacaine at a dose of 22.5 mg (3 ml) per hour. Patients were randomly assigned to one of two groups. In the SEB group (n = 8), patients received one third of the hourly dose every 20 min as a bolus. In the CEI group (n = 8), the hourly dose was administered as a continuous infusion. Analgesia was assessed by rest pain scored by a visual analog scale and pinprick to determine the number of separately blocked spinal segments on each side of the body. Doses of rescue medication for pain were also recorded.

Results

The median number of blocked spinal segments was 19.5 (range, 18-24) in the SEB group and 11.5 (range, 10-18) in the CEI group (P < 0.001). The median difference in the number of blocked segments between the right and left sides was 0 (range, 0-1) in the SEB group and 2 (range, 0-6) in the CEI group (P < 0.04). No patients in the SEB group but one patient in the CEI group required rescue medication for pain. The visual analog scale pain score was 0 in both groups except for one patient in the CEI group during the study period.

Conclusion

The SEB technique with ropivacaine provides superior epidural block compared with an identical hourly dose administered as a continuous infusion.
Remifentanil-induced Postoperative Hyperalgesia and Its Prevention with Small-dose Ketamine
Authors: Joly Vincent , Richebe Philippe , Guignard Bruno , Fletcher Dominique , Maurette Pierre , Sessler Daniel I. , Chauvin Marcel
Published: June 2005

Background

Remifentanil-induced secondary hyperalgesia has been documented experimentally in both animals and healthy human volunteers, but never clinically. This study tested the hypotheses that increased pain sensitivity assessed by periincisional allodynia and hyperalgesia can occur after relatively large-dose intraoperative remifentanil and that small-dose ketamine prevents this hyperalgesia.

Methods

Seventy-five patients undergoing major abdominal surgery were randomly assigned to receive (1) intraoperative remifentanil at 0.05 microg x kg(-1) x min(-1) (small-dose remifentanil); (2) intraoperative remifentanil at 0.40 microg x kg(-1) x min(-1) (large-dose remifentanil); or (3) intraoperative remifentanil at 0.40 microg x kg(-1) x min(-1) and 0.5 mg/kg ketamine just after the induction, followed by an intraoperative infusion of 5 microg x kg(-1) x min(-1) until skin closure and then 2 microg x kg(-1) x min(-1) for 48 h (large-dose remifentanil-ketamine). Pain scores and morphine consumption were recorded for 48 postoperative hours. Quantitative sensory tests, peak expiratory flow measures, and cognitive tests were performed at 24 and 48 h.

Results

Hyperalgesia to von Frey hair stimulation adjacent to the surgical wound and morphine requirements were larger (P < 0.05) and allodynia to von Frey hair stimulation was greater (P < 0.01) in the large-dose remifentanil group compared with the other two groups, which were comparable. There were no significant differences in pain, pressure pain detection threshold with an algometer, peak flow, cognitive tests, or side effects.

Conclusion

A relatively large dose of intraoperative remifentanil triggers postoperative secondary hyperalgesia. Remifentanil-induced hyperalgesia was prevented by small-dose ketamine, implicating an N-methyl-d-aspartate pain-facilitator process.
Financial Implications of a Hospital’s Specialization in Rare Physiologically Complex Surgical Procedures
Authors: Wachtel Ruth E. , Dexter Franklin , Lubarsky David A.
Published: June 2005

Background

The authors previously identified a hospital that has a unique role in its region for surgical care. In children aged 0-2 yr, the hospital performed 64% of all physiologically complex procedures statewide (>or= 8 American Society of Anesthesiologists Relative Value Guide basic units). For all age groups combined, 48% of the physiologically complex procedures performed at that hospital were rare, defined as < 1/workday statewide.

Methods

The authors tested the hypothesis that financially important differences can result from performing relatively large numbers of such specialized procedures. Methods were developed to compare contribution margin (revenue from facility and professional fees minus variable costs) per operating room hour (CM/OR hour) between patient groups and different types of surgical procedures.

Results

CM/OR hour was significantly larger by a financially important amount (> 250 dollars/OR hour) for pediatric versus geriatric patients (P <or= 0.002), primarily because of higher professional reimbursements, with no difference in hospital reimbursements. Unexpectedly, CM/OR hour was also significantly greater by at least 250 dollars when a rare procedure was involved (P < 0.001 for all ages combined), primarily because of greater hospital reimbursements. For cases involving implant charges of 10,000 dollars or greater, overall CM/OR hour was negative because increased revenues did not compensate for the high variable costs.

Conclusions

Other hospitals can use these methods to perform a similar analysis of the financial impact of those patient populations or surgical procedures that are unique to their own roles in their regional healthcare systems, and to identify the sources of financial losses and gains experienced by the hospital.
Primer of Postoperative Pruritus for Anesthesiologists
Authors: Waxler Beverly , Dadabhoy Zerin P. , Stojiljkovic Ljuba , Rabito Sara F. , Warltier David C.
Published: June 2005

Postoperative itching is an important problem in the postoperative care unit. Pruritus after surgery may be drug induced (including intrathecal opioids) or secondary to a preexisting systemic disease. Mechanisms of itching are complex and not completely understood. The purpose of this review is to highlight new discoveries in pathways and mechanisms of pruritus and to summarize up-to-date knowledge about treatment of itching after surgery. More basic and clinical studies are needed to address the effects of drugs on specific receptors and improve the treatment of postoperative pruritus.
The McGill Pain Questionnaire
Authors: Melzack Ronald , Raja Srinivasa N.
Published: June 2005

On the language of pain. By Ronald Melzack, Warren S. Torgerson. Anesthesiology 1971; 34:50-9. Reprinted with permission. The purpose of this study was to develop new approaches to the problem of describing and measuring pain in human subjects. Words used to describe pain were brought together and categorized, and an attempt was made to scale them on a common intensity dimension. The data show that: 1) there are many words in the English language to describe the varieties of pain experience; 2) there is a high level of agreement that the words fall into classes and subclasses that represent particular dimensions or properties of pain experience; 3) substantial portions of the words have approximately the same relative positions on a common intensity scale for people who have widely divergent backgrounds. The word lists provide a basis for a questionnaire to study the effects of anesthetic and analgesic agents on the experience of pain.
Positive lymphocyte transformation test in a patient with allergic contact dermatitis of the scalp after short‐term use of topical minoxidil solution
Authors: Hagemann Tobias , Schlütter‐Böhmer Brigitte , Allam Jean‐Pierre , Bieber Thomas , Novak Natalija
Published: June 2005

Topical 2,4‐diamino‐6‐piperidinopyrimidine‐3‐oxide (minoxidil) solution has been widely used for the treatment of androgenetic alopecia for over 15 years now and the substance is currently approved for this indication in 2% and 5% formulation. Typical side effects of this topical treatment include irritative dermatitis going along with pruritus, erythema, scaling and dryness, which occur especially at the onset of the therapy. In some cases, allergic contact dermatitis or exacerbation of seborrhoic dermatitis has been reported. While most of the patients with allergic contact dermatitis described in the literature showed a positive sensitization to the vehicle substance propylene glycol evaluated by patch testing, reactions to the active ingredient minoxidil are rare. Here, we report a case of allergic sensitization to minoxidil, which we evaluated and differentiated from an irritative reaction by a combination of patch testing and lymphocyte transformation test. The differentiation of allergic and irritative adverse effects and the identification of the causative allergen are of major relevance for the proceeding and adjustment of the therapy. Patients with sensitizations against propylene glycol are candidates for preparations with alternative solvents but can proceed treatment with minoxidil. In contrast, patients with allergies to the active ingredient itself are no longer candidates for treatment with minoxidil and should undergo alternative therapeutic options.
A temporary henna tattoo causing hair and clothing dye allergy
Authors: Matulich Jacqueline , Sullivan John
Published: June 2005

Contact dermatitis following the application of temporary paint‐on henna tattoos indicates a potentially serious problem of active sensitization. We describe 2 cases involving sisters who travelled to Bali together and acquired a temporary black henna tattoo to the lower back region. Both sisters subsequently developed a contact dermatitis at the tattoo site, the dermatitis disseminating in one sister. There was persistent hyperpigmentation at the tattoo site in both sisters several months after the application. Patch testing revealed a positive reaction to para‐phenylenediamine (PPD) in both sisters. One sister also showed reactions to other hair dyes and to multiple organic dyes. Allergic contact dermatitis to PPD contained in temporary henna tattoos is an increasing problem worldwide, with cross‐reaction to related compounds and permanent skin changes, a frequent consequence of sensitization to this significant allergen.
Allergic contact dermatitis from natural rubber latex in atopic dermatitis and the risk of later Type I allergy
Authors: Guillet G. , Guillet M. H. , Dagregorio G.
Published: June 2005

The aims of the study were to assess whether contact dermatitis in children could be due to a delayed hypersensitivity reaction to natural rubber latex (NRL) and to define risk factors for later occurrence of Type I hypersensitivity to this allergen. Among 1800 children investigated for contact dermatitis, 55 were referred on suspicion of rubber allergy and had patch tests to NRL, as well as prick tests and blood tests for specific immunoglobulin E (IgE). A 2‐year follow‐up was then carried out. Delayed hypersensitivity to NRL was confirmed in 32 children. Patch testing with NRL proved to be positive, and clinical improvement confirmed the diagnosis and relevance of patch tests. 30 of these 32 patients had associated atopic dermatitis (AD). Prick tests and blood tests for specific IgE to latex were negative at the time of diagnosis. A 2‐year follow‐up showed that 10 of 27 patients presenting initially with a positive patch test without associated Type I sensitization later developed immediate hypersensitivity. Children with AD are at high risk for allergy to NRL protein. Exclusion of this allergen should be strongly advised in atopics because of the dual risk of dermatitis and later evolution into severe Type I hypersensitivity.
Interphase fluorescence in situ hybridization with an IGH probe is important in the evaluation of patients with a clinical diagnosis of chronic lymphocytic leukaemia
Authors: Nowakowski G. S. , Dewald G. W. , Hoyer J. D. , Paternoster S. F. , Stockero K. J. , Fink S. R. , Smoley S. A. , Remstein E. D. , Phyliky R. L. , Call T. G. , Shanafelt T. D. , Kay N. E. , Zent C. S.
Published: June 2005

Translocations involving IGH are common in some lymphoid malignancies but are believed to be rare in chronic lymphocytic leukaemia (CLL). To study the clinical utility of fluorescence in situ hybridization (FISH) for IGH translocations, we reviewed 1032 patients with a presumptive diagnosis of CLL. Seventy‐six (7%) patients had IGH translocations. Pathology and clinical data were available for the 24 patients evaluated at the Mayo Clinic. Ten (42%) patients had IGH/cyclin D1 fusion and were diagnosed with mantle cell lymphoma (MCL). The immunophenotype was typical of MCL in three of these patients and atypical for MCL in seven patients. One patient had biclonal disease with typical MCL and CLL with IGH/BCL‐2. Eleven (46%) patients had IGH/BCL‐2 fusion including the patient with biclonal disease. Two of these patients had leukaemic phase follicular lymphoma and nine patients had CLL. The median progression‐free survival of patients with CLL and IGH/BCL‐2 translocation was 20·6 months. The two patients with IGH/BCL‐3 fusion (one of these also had IGH/BCL‐11a) had rapid disease progression. The IGH partner gene was not identified in two patients. We conclude that use of an IGH probe in FISH analysis of monoclonal B‐cell lymphocytosis improves diagnostic precision and could have prognostic value in patients with CLL.
Low‐dose cyclophosphamide conditioning for haematopoietic cell transplantation from HLA‐matched related donors in patients with Fanconi anaemia
Authors: Zanis‐Neto J. , Flowers M. E. D. , Medeiros C. R. , Bitencourt M. A. , Bonfim C. M. , Setúbal D. C. , Funke V. , Sanders J. , Deeg H. J. , Kiem H. P. , Martin P. , Leisenring W. , Storb R. , Pasquini R.
Published: June 2005

Allogeneic haematopoietic cell transplantation (HCT) is effective therapy for Fanconi anaemia (FA). FA patients do not tolerate conditioning with 200 mg/kg of cyclophosphamide (Cy), typically used in aplastic anaemia. We previously published results of studies in which Cy doses were gradually reduced from 200 to 100 mg/kg. Here we update results of the initial studies and report data on 30 new patients conditioned with Cy either at 80 mg/kg (n = 7) or at 60 mg/kg (n = 23), given over 4 days before HCT from human leucocyte antigen‐matched related donors. Methotrexate and cyclosporine were given for graft‐versus‐host disease (GVHD) prophylaxis. All seven patients given Cy at 80 mg/kg and 21 of 23 given Cy at 60 mg/kg had sustained engraftment, while two patients, both with clonal cytogenetics abnormalities, experienced graft failure. Grades 2–3 acute GVHD rates were 57% and 14% for patients given the higher and lower Cy doses, respectively (P = 0·001). Four patients given Cy at 80 mg/kg and 22 given Cy at 60 mg/kg were alive at a median of 47 (44–58) months and 16 (3–52) months, respectively. Cy at 60 mg/kg has acceptable toxicities, low rates of GVHD, and is sufficient for engraftment of related grafts in most FA patients.
CD34+ cell selection is required to assess HOXA9 expression levels in patients with myelodysplastic syndrome
Authors: Heinrichs Stefan , Berman Jason N. , Ortiz Taylor M. , Kornblau Steven M. , Neuberg Donna S. , Estey Elihu H. , Thomas Look A.
Published: June 2005

Overexpression of HOXA9 is linked to the molecular pathogenesis of acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS), conferring a poor prognosis. HOXA9 expression levels were analysed in the diagnostic bone marrow (BM) samples of 13 MDS patients. HOXA9 was expressed by CD34+ BM cells at median levels 3·1‐fold higher than in CD34− cells from the same patient and at median levels 4·3‐fold higher than in CD34+ cells from healthy donors. These results indicate that CD34+ cell selection is required to accurately assess the expression levels of HOXA9 and related genes in the multipotential malignant progenitor cells of MDS patients.
Impaired bradykinin response to ischaemia and exercise in patients with mild congestive heart failure during angiotensin‐converting enzyme treatment. Relationships with endothelial function, coagulation and inflammation
Authors: Cugno Massimo , Agostoni Piergiuseppe , Mari Daniela , Meroni Pier Luigi , Gregorini Luisa , Bussotti Maurizio , Anguissola Gian Battista , Donatelli Francesco , Nussberger Jürg
Published: June 2005

Inflammation and endothelial dysfunction play important roles in the pathophysiology of congestive heart failure (CHF), and the peptide bradykinin, generated during inflammation, may act as a defence mechanism by inducing vasodilation. Plasma bradykinin levels are increased in experimental heart failure but low in patients with advanced chronic CHF despite treatment with angiotensin‐converting enzyme (ACE) inhibitors. It is not currently known how bradykinin behaves in less severe phases of CHF controlled by long‐term ACE inhibitor treatment. We studied 10 male patients with clinically stable chronic CHF [New York Heart Association (NYHA) class II] on long‐term ACE inhibitor treatment and 10 normal sex‐ and age‐matched control subjects. High performance liquid chromatography/radioimmunoassay methods were used to evaluate plasma levels of bradykinin in relation to an array of parameters of endothelial function, coagulation and inflammation before and after stimuli of forearm arterial occlusion and physical exercise. CHF patients had higher levels of bradykinin (P = 0·008), activated factor XII (P = 0·049), interleukin‐6 (P = 0·050) and tumour necrosis factor receptor II (sTNFRII) (P = 0·026) than controls. Arterial occlusion and exercise significantly increased bradykinin and von Willebrand factor levels in controls but not in CHF patients. The increase in brachial artery diameter after arterial occlusion was less in CHF patients (P = 0·036) and inversely related to baseline plasma levels of bradykinin (r = −0·855, P = 0·002) and sTNFRII (r = −0·780, P = 0·008). NYHA class II CHF patients during long‐term treatment with ACE inhibitors have increased bradykinin levels and signs of inflammation. They are unable to respond adequately to stimuli of ischaemia and physical exercise which both require vasodilation.
Osteosclerosis in advanced chronic idiopathic myelofibrosis is associated with endothelial overexpression of osteoprotegerin
Authors: Bock Oliver , Loch Gero , Schade Ulrika , Büsche Guntram , von Wasielewski Reinhard , Wiese Birgitt , Kreipe Hans
Published: June 2005

Advanced chronic idiopathic myelofibrosis (IMF) with osteosclerosis and increase and thickening of bone trabeculae is typically contrasted by the absence or sparse presence of osteoclasts. Because osteoclast formation can be inhibited by osteoprotegerin (OPG) we investigated OPG expression in IMF with severe fibrosis and osteosclerosis, which expressed significantly higher (up to 71‐fold) OPG mRNA levels when compared with prefibrotic cellular IMF and control cases. The receptor activator of nuclear factor kappaB ligand (RANKL), a positive regulator of osteoclast differentiation and putative antagonist of OPG was overexpressed by up to 34‐fold exclusively in advanced IMF. Case‐specific calculation of the RANKL/OPG ratio in advanced IMF showed a wide range without significant differences when compared with the prefibrotic IMF and non‐neoplastic haematopoiesis. Immunohistochemical detection of OPG protein revealed strong labelling of endothelial cells within proliferating vessels in fibrotic IMF and heterogeneously labelled megakaryocytes, and fibroblasts. Osteosclerosis and impaired osteoclast function in IMF appears to be associated with upregulated endothelial OPG expression but concomitant reduction of the antagonist RANKL could not be demonstrated. We conclude that osteosclerosis in IMF is associated with increased endothelial OPG expression without concomitant RANKL downregulation.
Co‐operative signalling mechanisms required for erythroid precursor expansion in response to erythropoietin and stem cell factor
Authors: Arcasoy Murat O. , Jiang Xiaohong
Published: June 2005

The regeneration of circulating red blood cells in response to anaemia associated with blood loss or haemolysis involves an increased rate of erythropoiesis and expansion of proerythroblasts, the bone marrow precursor cells that terminally differentiate into mature erythrocytes. This study investigated the mechanisms by which erythropoietin (Epo) and stem cell factor (Scf) modulate the expansion of proerythroblasts. Homogenous populations of primary human proerythroblasts were generated in liquid cultures of CD34+ cells. In serum‐free cultures, proerythroblasts failed to survive in the presence of Epo or Scf alone, but exhibited synergistic proliferation in response to combined Epo and Scf treatment, exhibiting one‐log expansion in 5 d. Intracellular signal transduction in response to Epo and Scf revealed that tyrosine phosphorylation of signal transducers and activators of transcription (Stat) 5, a downstream target for the non‐receptor tyrosine kinase, Janus kinase 2 (Jak2), was mediated by Epo but not Scf. The mitogen‐activated protein kinases (MAPKs) extracellular regulated kinase (Erk) 1–2 were phosphorylated in response to either Epo or Scf. Phosphorylation of Akt, a signalling molecule downstream of phosphatidylinositol 3‐kinase (PI3K), was observed following Scf but not Epo treatment. To determine the contribution of specific signalling pathways to synergistic expansion of proerythroblasts in response to co‐operative effects of Epo and Scf, cells were treated with kinase inhibitors targeting Jak2, PI3K and MAPK kinase. There was a significant, dose‐dependent inhibition of proerythroblast expansion in response to all three kinase inhibitors. In conclusion, Epo‐ and Scf‐mediated co‐operative, synergistic expansion of primary erythroid precursors requires selective activation of multiple signalling pathways, including the Jak‐Stat, PI3K and MAPK pathways.
Vaccination of patients with haematological malignancies with one or two doses of influenza vaccine: a randomised study
Authors: Ljungman Per , Nahi Hareth , Linde Annika
Published: June 2005

An open, randomised study was performed to determine whether two doses of influenza vaccine were more effective than one to elicit an immune response in 70 patients with haematological malignancies. The responses were not improved by two doses compared with one (influenza A virus serotypes H1/N1 18% vs. 22% and H3/N2 26% vs. 14%; influenza B 25% vs. 22%). The results were similar in patients with ongoing and discontinued therapy. Patients treated with monoclonal antibodies for lymphoma had very poor responses. We conclude that two doses of influenza vaccine do not improve the antibody response in patients with haematological malignancies.
The measurement of urinary hydroxyurea in sickle cell anaemia
Authors: Neil Dalton R , Turner Charles , Dick Moira , Height Susan E , Awogbade Moji , Inusa Baba , Okpala Iheanyi , O'Driscoll Sandra , Thein Swee Lay , Rees David C
Published: June 2005

Hydroxyurea is increasingly used in the treatment of sickle cell disease (SCD) although there is little evidence on how best to monitor treatment and compliance. It is also not known why 10–50% patients do not benefit from the drug and whether some of this resistance is because of pharmacokinetic factors. We have developed an assay using mass spectrometry (MS) to measure urinary concentrations of hydroxyurea. We have used this assay to study 12 children and six adults with SCD taking hydroxyurea and found that urinary hydroxyurea was present for at least 12 h following tablet ingestion. Thirty‐five urine samples were analysed that were expected to contain hydroxyurea, based on the reported timing of the last dose and hydroxyurea was detected in 29 (83%) of these. There were also marked differences in urinary hydroxyurea concentrations, suggesting pharmacokinetic variability may explain some of the differences in response to hydroxyurea. Urine samples were also analysed by MS for penicillin metabolites and 43 of the 57 (75%) contained phenoxyacetate, suggesting the ingestion of penicillin within the last 12 h. These assays are potentially useful to study hydroxyurea metabolism further, develop optimal dosing regimes and monitor compliance with treatment.
A novel classification of tumour budding in colorectal cancer based on the presence of cytoplasmic pseudo‐fragments around budding foci
Authors: Shinto E , Mochizuki H , Ueno H , Matsubara O , Jass J R
Published: June 2005

Aims : Tumour budding is an adverse prognostic factor in colorectal cancer (CRC). We have investigated the significance of cytoplasmic fragments occurring in the immediate vicinity of tumour budding foci.

Methods and results : Seventy‐three CRCs with high‐grade budding (> 10 budding foci in a × 20 objective field) were classified according to extent of budding (10–19 versus 20+ foci) and by the presence or absence of cytoplasmic fragments identified by immunostaining for cytokeratin. In serial sections, cytoplasmic fragments were shown to be dendritic cell processes in continuity with budding tumour cells and were renamed pseudo‐fragments. Cytoplasmic pseudo‐fragments, but not extent of budding, were associated with aberrant expression of β‐catenin (P = 0.045) and laminin‐5 γ2 (P < 0.0001), and with absent peritumoral lymphocytic infiltration (P = 0.0077). Cytoplasmic pseudo‐fragments had a stronger association with infiltrating growth pattern (P = 0.0014) than extent of tumour budding (P = 0.014). There was no association between extent of budding and cytoplasmic pseudo‐fragments (P = 0.12).

Conclusions : Cytoplasmic pseudo‐fragments may be a marker for an activated budding phenotype that is associated with cell motility and increased invasiveness in CRC and is independent of the extent of budding.
Extrafollicular proliferation of B cells in the absence of follicular hyperplasia: a distinct reaction pattern in lymph nodes correlated with primary or recall type responses
Authors: Brighenti A , Andrulis M , Geissinger E , Roth S , Müller‐Hermelink H K , Rüdiger T
Published: June 2005

Aims : Extrafollicular activation of B cells is rarely observed in human lymph nodes. The aim of this study was to extensively analyse the expression of surface molecules and transcription factors in four such cases, comparing them with follicular B cells and medullary cord plasma cells.

Methods and results : Various combinations of B‐cell‐related surface markers and transcription factors were studied by triple immunofluorescence. While in the germinal centre, reactive immunoglobulin production occurred exclusively in non‐proliferating cells, in extrafollicular activation proliferation of B cells and immunoglobulin production coexisted. In two of these cases proliferating cells were mainly IgG+CD27+, i.e. derived from class‐switched postgerminal centre memory B cells. Some of these cells expressed CD30. In the other two cases, immunoglobulin‐forming cells were non‐class‐switched IgM+CD27– B cells, representing a primary expansion of naive B cells.

Conclusions : Extrafollicular B‐cell activation is the morphological correlate of rapid B‐cell responses that do not involve the germinal centres. It is pathogenetically heterogeneous, comprising primary responses that occur prior to, or independent of, germinal centre reaction or memory cell activation in recall responses.
Demographic and pathological characteristics of serrated polyps of colorectum
Authors: Higuchi T , Sugihara K , Jass J R
Published: June 2005

Aims : To characterize a series of colorectal polyps, focusing on the clinicopathological features of serrated adenoma (SA), mixed polyp (MP) and the recently recognized sessile serrated adenoma (SSA).

Methods and results : Eight hundred and ninety‐one conventional adenomas (AD), 298 hyperplastic polyps (HP), 27 SSA, 10 MP and 24 traditional SA were obtained from patients during colonoscopic examination. SSA were more likely to be proximally located than other polyps. All SA, MP and SSA and a randomly selected subset of HP (n = 61) and ADs (n = 93) were assessed for expression of mucin, MLH1, MGMT, and Ki67. SSA expressed more MUC5AC than either HP or SA. Loss of MLH1 was not observed in any serrated polyps and in only one AD. Loss of MGMT occurred in 13% of AD, and showed no correlation with histological type, size or location. Loss of MGMT occurred in 24% of SSA, MP and SA (combined), and was more frequent in proximal lesions and larger lesions. SSA had a higher proliferative index than HP. In MP, the proliferative index of the non‐dysplastic component was closer to HP than SSA, while the dysplastic component was intermediate between SA and AD.

Conclusions : SSA differ from other serrated polyps of colorectum in terms of location, morphology and immunophenotype.
Stem cell pluripotency factor NANOG is expressed in human fetal gonocytes, testicular carcinoma in situ and germ cell tumours
Authors: Hoei‐Hansen C E , Almstrup K , Nielsen J E , Brask Sonne S , Graem N , Skakkebaek N E , Leffers H , Rajpert‐De Meyts E
Published: June 2005

Aims : NANOG is a key regulator of embryonic stem cell (ESC) self‐renewal and pluripotency. Our recent genome‐wide gene expression profiling study of the precursor of testicular germ cell tumours, carcinoma in situ testis (CIS), showed close similarity between ESC and CIS, including high NANOG expression. In the present study we analysed the protein expression of NANOG during normal development of human testis and in a large series of neoplastic/dysgenetic specimens.

Methods and results : We detected abundant expression of NANOG in CIS and in CIS‐derived testicular tumours with marked differences; seminoma and embryonal carcinoma were strongly positive, differentiated somatic elements of teratoma were negative. We provide evidence for the fetal origin of testicular cancer as we detected strong expression of NANOG in fetal gonocytes up to gestational week 20, with subsequent down‐regulation occurring earlier than for OCT‐4. We detected no expression at the protein level in normal testis.

Conclusions : NANOG is a new marker for testicular CIS and germ cell tumours and the high level of NANOG along with OCT‐4 are determinants of the stem cell‐like pluripotency of the preinvasive CIS cell. Timing of NANOG down‐regulation in fetal gonocytes suggests that NANOG may act as a regulatory factor up‐stream to OCT‐4.
Polymorphism of human leukocyte antigen‐DRB1, ‐DQB1, and ‐DPB1 genes of Shandong Han population in China
Authors: Zhou L. , Lin B. , Xie Y. , Liu Z. , Yan W. , Xu A.
Published: June 2005

Abstract:  In the present study, polymerase chain reaction‐sequence‐based typing (PCR‐SBT) was used to analyze human leukocyte antigen (HLA)‐DRB1, ‐DQB1, and ‐DPB1 alleles of 98 unrelated healthy Shandong Han individuals. A total of 60 alleles, in which 28 in DRB1, 15 in DQB1 and 17 in DPB1 were found. Among the 28 detected DRB1 alleles, DRB1*150101, DRB1*070101, DRB1*090102, DRB1*120201, and DRB1*080302 were commonly observed, with frequencies of 16.3%, 11.2%, 10.2%, 8.2%, and 5.6%, respectively. The most predominant DQB1 allele was DQB1*030101/0309 with the frequency of 20.4%, followed by DQB1*0201/0202 (14.8%), DQB1*0602 (14.3%), DQB1*030302 (12.2%), and DQB1*060101/060103 (10.7%). Of the 17 detected DPB1 alleles, DPB1*0501 was the most frequent allele with the frequency of 37.2%. DPB1*020102 (18.4%), DPB1*040101 (11.2%), DPB1*0402 (7.1%), and DPB1*1701 (6.6%) were also very frequent alleles. A total of 53 estimated DRB1‐DQB1 two‐locus haplotypes were observed in Shandong Han population, of which DRB1*150101‐DQB1*0602 was the most predominant, followed by DRB1*090102‐DQB1*030302, DRB1*070101‐DQB1*0201/0202 DRB1*120201‐DQB1*030101/0309, and DRB1*080302‐ DQB1*060101/060103. The distribution of the HLA class II alleles and haplotypes frequencies as well as the dendrogram showed that the Shandong Han population belongs to the northern group of Chinese. The data have implications for anthropological studies and disease associations.
Identification of a new allele, HLA‐DRB1*1366*
Authors: Milia S. , Lai S. , Valentini T. , Testi M. , Cappai L. , Moscetti A. , Mariani M. , Alba F. , Carcassi C.
Published: June 2005

Abstract:  High‐resolution polymerase chain reaction sequence‐specific primer typing of the human leucocyte antigen (HLA)‐DRB1 gene of an Italian patient candidate for bone marrow transplantation revealed a new allelic variant of HLA‐DRB1*13. The sequence was named DRB1*1366, and comparison with previously described DRB1 alleles demonstrated the two closely related sequences were HLA‐DRB1*1330 and HLA‐DRB1*130302.
HLA genes in Portugal inferred from sequence‐based typing: in the crossroad between Europe and Africa
Authors: Spínola H. , Middleton D. , Brehm A.
Published: June 2005

Abstract:  The human leukocyte antigen‐A (HLA‐A), ‐B and ‐DRB1 polymorphism was examined in the Portuguese population, discriminating between North, Centre and South inhabitants. All data were obtained at high‐resolution level, using sequence‐based typing. The most frequent allele at each locus was A* 020101 (26%), B* 440301 and B* 510101 (12% each) and DRB1* 070101 (15%). The predominant three‐locus haplotype was A*020101‐B*440301‐DRB1*070101 (3.1%), highly frequent in North Portugal (5.4%), lower in Centre (2%) and absent in the South. The present study demonstrates that the Portuguese population has been genetically influenced by Europeans and North Africans, via several historic immigrations. North Portugal seems to concentrate, probably due to the pressure of Arab expansion, an ancient genetic pool originated from several North Africans and Europeans, influences throughout millenniums. South Portugal shows a North African genetic influence, probably of recent origin by means of Berbers accompanying Arab expansion. We found that Centre Portugal is the distribution limit of some alleles and haplotypes that characterize the North or the South of the country. Despite North, Centre and South Portugal not being significantly different in allele frequencies, this study shows that HLA allele and haplotype frequencies are not homogeneous in the country. North and South Portugal show more similarity to North Africans in opposition to Centre which appears closer to Europeans.
Primary frontal sinus aspergillosis: an uncommon occurrence
Authors: Panda Naresh Kumar , Ekambar Eshwara Reddy C.
Published: June 2005

Primary frontal sinus aspergillosis is extremely uncommon with only few cases reported in the English literature. Isolated frontal sinus aspergillosis is usually asymptomatic and produces symptoms due to orbital or intracranial involvement. We report two cases of primary frontal sinus aspergillosis, presenting as frontoethmoidal mucocele and mimicking a ‘Pott's puffy tumor,’ respectively. Forehead swelling produced by frontal sinus aspergillosis will be the first to be reported in the English literature.
Two cases of cutaneous cryptococcosis
Authors: Xiujiao Xia , Ai'e Xu
Published: June 2005

We report two cases of cutaneous cryptococcosis in male patients without underlying disease. Case 1 had a granulomatous mass on his right neck, gradually enlarging for 3 months. After the mass was debrided surgically in a hospital, the incision wound gradually developed into a severe ulceration. Mycological examination revealed Cryptococcus neoformans infection. It was significant that histopathology of both pre‐surgery granuloma and post‐surgery ulceration revealed thick‐walled spores with thick capsule. Chest X‐ray revealed a shadow in the left lower lung. After treatment with amphotec for 21 days, the lesion healed. Case 2 had an approximately 2 × 2 cm solitary dull nodule on his right thigh, which had been present for 8 months. Mycological examination confirmed that the lesion was caused by C. neoformans. The patient's ratio of peripheral blood CD4+ cell was slightly reduced. After 14 days of treatment with oral fluconazole, followed by oral itraconazole for 2 months, mycological and clinical cure were achieved. The two isolates were identified as C. neoformans var. gattii serotype C and C. neoformans var. grubii serotype A.
Identification of Malassezia species from Tunisian patients with pityriasis versicolor and normal subjects
Authors: Salah S. Ben , Makni F. , Marrakchi S. , Sellami H. , Cheikhrouhou F. , Bouassida S. , Zahaf A. , Ayadi A.
Published: June 2005

Background: The genus Malassezia (Pityrosporum), recognized as a member of microbiological flora of the skin in humans and warm‐blooded animals, has been recently revised to include 10 Malassezia species. The aim of the study was the isolation, identification and analysis of Malassezia species distribution in skin of healthy volunteers and lesions of pityriasis versicolor (PV). Material and methods: Specimens were taken from 100 patients with PV and 30 healthy volunteers. Cultures were made in modified Dixon agar medium and the isolates were identified by morphological and physiological methods: macroscopy, microscopy, catalase, β‐glucosidase and lipid assimilation tests. Results: Malassezia globosa was the predominant species in lesional skin of PV (65%). It was isolated alone in 47% of cases and associated in 18% with M. furfur (13%) or M. sympodialis (5%). In healthy skin M. globosa was found alone in 7.77% and associated in 15.54%, respectively, with M. furfur (4.44%), M. sympodialis (4.44%), M. restricta (3.33%) and M. slooffiae (1.11%). Conclusion: From these findings it was suggested that M. globosa presents the main species implicated in the pathogenicity of PV and M. furfur as the second agent of importance.
Pharmacological properties and clinical efficacy of a recently licensed systemic antifungal, caspofungin
Authors: Maschmeyer Georg , Glasmacher Axel
Published: June 2005

Caspofungin, a semisynthetic derivative of the pneumocandin B0, is the first licensed compound of a new class of antifungal agents, the echinocandins. It attacks the fungal cell by selective inhibition of the beta‐(1,3)‐d‐glucan synthase, which is not present in mammalian cells. In vitro studies have indicated a potent fungicidal effect on Candida species, and in vivo studies in immunocompromised animals with invasive candidiasis demonstrated a favourable outcome. In randomized clinical trials in patients with oropharyngeal/oesophageal and invasive candidiasis, caspofungin was at least as effective as amphotericin B deoxycholate, yet showed a significantly superior safety profile. Of patients with invasive aspergillosis refractory to or intolerant of other antifungal agents, 45% showed a partial or complete response to caspofungin given as a salvage treatment. Also, it demonstrated comparable clinical efficacy but superior tolerability in the empirical antifungal therapy in neutropenic patients compared with liposomal amphothericin B. Caspofungin has an excellent tolerability and a low potential for drug interactions. Thus, caspofungin represents an interesting and clinically valuable new antifungal drug that broadens the available therapeutic armamentarium for the treatment of invasive fungal infections.
Stromal cells in hemangioblastoma: Neuroectodermal differentiation and morphological similarities to ependymoma
Authors: Ishizawa Keisuke , Komori Takashi , Hirose Takanori
Published: June 2005

The histogenesis of stromal cells in hemangioblastoma is inconclusive despite a long‐term controversy. An immunohistochemical and ultrastructural study was conducted for 17 cases of cerebellar hemangioblastoma. A wide range of immunohistological markers, targeting epithelial, mesenchymal, endothelial and neuroectodermal tissues, was used. In all cases, the microscopic hallmark characterizing hemangioblastomas, that is, lipid‐containing stromal cells and a fine capillary network, known as a reticular variant, was noted. Stromal cells showed a variable immunoreactivity for neuroectodermal markers, such as S‐100 protein, CD56, CD57, CD99, and neuron‐specific enolase. This result, in conjunction with the absence of immunoreactivity for epithelial, mesenchymal, and endothelial markers, likely suggests neuroectodermal differentiation of stromal cells. In three cases, another component, known as a cellular variant, where epithelioid tumor cells were arranged in nests encircled by capillaries and/or in pseudorosette‐like structures, was noted. Glial fibrillary acidic protein‐immunoreactivity, which was totally absent in cases only showing the reticular pattern, was noted in two of them, suggesting a distinctive sign of glial differentiation in a proportion of hemangioblastomas. Ultrastructurally, microvilli‐like projections in intracytoplasmic vacuoles were demonstrated in stromal cells. This result, taken together with the neuroectodermal hypothesis of stromal cells, suggests that hemangioblastomas may occasionally exhibit morphological similarities to ependymomas.