Small bowel infarction associated with pancreatic glucagonoma

An 88 year old woman presented comatose, hypothermic and hyperglycaemic. She died soon after admission and at autopsy recent small bowel infarction was found. The superior mesenteric artery was encased in a dense pancreatic mass and there was marked luminal narrowing of the vessel. Histology revealed a pancreatic glucagonoma which had metastasized to colonic submucosa and serosa. Glucagonoma is a rare tumour and this presentation of small bowel infarction associated with pancreatic glucagonoma would appear to be a unique event.     

Delayed presentation and treatment of popliteal artery embolism.

In the course of reviewing a 10-year experience with popliteal artery embolism (PAE), two distinct patterns of clinical presentation were identified. In addition to those patients presenting with typical acute (symptom duration less than 7 days) arterial ischemia, a second group was identified who presented with more chronic symptoms. The present study was conducted to contrast the clinical factors and treatment of these two temporal patterns of presentation with PAE. Sixty PAEs in 58 patients were documented by the combination of angiography and/or exploration of the popliteal artery. Acute presentation (AP) was seen in 41 (68%) of these and delayed presentation (DP) was noted in 19 (32%) patients. Delayed presentation patients typically presented with a history of sudden onset of claudication or rest pain and a median symptom duration of 30 days. Eighty per cent of AP patients presented with immediately threatened limbs. Angiography was generally diagnostic of chronic popliteal embolism. In the acute group, 90% were treated with embolectomy alone, while 20% of the DP group required bypass grafting. However in two thirds of the DP group, embolectomy alone performed through a direct popliteal approach was possible. Current results with overall limb salvage (92%) and mortality (7%) represents a substantial improvement compared to the authors' previous experience with PAE. The current study suggests that as many as one third of patients with popliteal artery embolism may present in delayed fashion with chronic symptoms. Furthermore most of these patients can be treated with direct popliteal embolectomy alone with favorable results.     

Immunocytochemical application of monoclonal antibodies to rat liver glucocorticoid receptor

Seven per cent (10/145) of hybridomas raised against partially purified activated glucocorticoid receptor from rat liver produced monoclonal antibody to receptor. Six IgM secreting clones selected for further investigation bound equally well to activated and non-activated receptor from fresh rat liver, but significantly less well (11-25 per cent) to receptor from frozen rat liver. No interaction was found with oestrogen receptor from rat uterus but extensive cross reaction occurred with progesterone receptor. Although none of the antibodies bound to glucocorticoid receptor from human or porcine liver or lymphoid cells, several cross-reacted with mouse liver glucocorticoid receptor. Immunoelectroblotting of proteins from fresh and frozen rat liver cytosol showed the antibodies bound to 90,000 and 40,000 MW forms of receptor respectively. Immunostaining of both frozen and paraffin embedded sections of rat tissue showed that receptor is preserved during fixation and processing of tissues. Using both indirect immunoperoxidase and immunogold silver staining methods, the pattern of receptor staining observed correlates with the known glucocorticoid responsiveness of the tissues studied.     

A comparison of the Neuropen against standard quantitative sensory-threshold measures for assessing peripheral nerve function.

AIMS: To investigate the efficacy of the Neuropen, a new clinical device that assesses both pain and pressure perception, to evaluate peripheral nerve function in diabetic patients compared with standard clinical testing methods. METHODS: Peripheral nerve function was assessed in 124 diabetic patients attending a multidisciplinary diabetes clinic, using (i) the modified Neuropathy Disability Score (NDS), derived from assessment of vibration, pinprick (pain), temperature sensation plus ankle reflexes, and (ii) vibration perception threshold (VPT) measured at the hallux. Patients were stratified into various neuropathic groups according to their NDS score. In addition, nerve function was assessed using the Neuropen, a device combining a 10-g monofilament and a weighted Neurotip. Inability to feel sensation on either or both feet for each test of the Neuropen (i.e. the monofilament or the Neurotip) was defined as an abnormal response. RESULTS: The sensitivity of the Neuropen to detect neuropathy compared with the NDS (score > or = 6/10) was high using either an abnormal monofilament response (87.8%), an abnormal Neurotip response (91.8%) or a combination of the two (82.0%). Neuropen specificity improved, however, when the combination of abnormal monofilament and abnormal Neurotip responses was used (68%), rather than the individual tests (57% and 41%, respectively). CONCLUSIONS: The Neuropen is a sensitive device for assessing nerve function and may provide an inexpensive alternative screening method to identify patients with moderate to severe neuropathy.     

Correlation of continuous-wave Doppler spectral flow analysis with gross pathology in carotid stenosis

Preoperative continuous-wave Doppler spectral analysis was used to generate two parameters, peak frequency in the internal carotid artery (fmax) and the ratio of peak frequencies in the internal and common carotid arteries (carotid index). These were compared with direct measurement of residual lumen diameter in pathologic specimens obtained from carotid endarterectomy in 37 patients. Doppler shift frequency parameters were well correlated with residual lumen diameter when the latter was at least 1 mm. Residual lumens of less than or equal to 2 mm were found to have an fmax of greater than 7.5 kHz and a carotid index of greater than 3.8. If fmax was greater than 14 kHz or the carotid index was greater than 7, the residual lumen diameter was nearly always less than or equal to 1 mm. Thus, the severity of the stenosis correlated directly with Doppler shift frequencies. The length of stenoses did not affect the correlations.     

The effect of recombinant follicle stimulating hormone (Gonal-F) on endogenous luteinizing hormone secretion in women

Parenteral administration of follicle stimulating hormone (FSH) has been shown to lower luteinizing hormone (LH) concentrations in women undergoing ovulation induction. This study was designed to explore the physiological mechanism of this effect. Seven healthy women were recruited into a double-blind placebo-controlled study. LH secretion, after the administration of variable i.v. boluses (37.5, 75 and 150 IU) of recombinant FSH (Gonal-F), was evaluated. LH was measured at 10 min intervals for 2 h before and 4 h after the FSH/placebo infusion. LH pulse frequency and amplitude were evaluated and there was no significant difference between control and trial cycles for each subject. A linear regression analysis revealed that in the group receiving 150 IU FSH, the mean plasma LH concentration decreased significantly due to a reduction tonic LH secretion. This could be a result of the suppression of secretion or an alteration of clearance. This decrease was not seen in the other dosage groups, revealing that above a dosage threshold, FSH reduced non-pulsatile LH secretion. Therefore the effect of FSH in this study exposed the likely presence of two components of LH concentration: an FSH-sensitive, non-pulsatile tonic secretion and a gonadotrophin-releasing hormone-stimulated, pulsatile release that is unaffected by FSH. Although an indirect effect involving ovarian regulation is not excluded, the rapidity of the effect suggests that FSH acts directly on the pituitary gland.      

Idiopathic chronic ulcerative enteritis: a report of two cases

Idiopathic chronic ulcerative enteritis (ICUE) is considered by some physicians to be a variant of sprue. Two patients being treated at our hospital for nonspecific abdominal symptoms had abnormal findings from a small-bowel series; at surgery, an ulcerating process involving the jejunum was found. Clinical, radiological, and pathological findings in these cases suggest that ICUE is a distinct entity.     

Different ω-conotoxins mark the development of Swiss Webster mouse cortex suggesting N-Type voltage sensitive calcium channel subtypes

ω-GVIA conotoxin has been used to mark presynaptic N-type voltage sensitive calcium channels (VSCC).³,¹³,¹⁹,^21–23 Litzinger et al.⁹ used ω-conotoxin binding to describe a critical period of neurodevelopment in Swiss Webster mice between postnatal days (PND) 11 and 14, which appears to be important to the initiation of proper final development of the central nervous system. In this study, we compare how three different ω-conotoxins (i.e. GVIA from Conus geographus, MVIIA from Conus magus, and RVIA from Conus radiatus) mark N-type VSCC during this critical period in Swiss Webster mouse cortex. ¹²⁵I-GVIA was bound to Swiss Webster mouse cortex synaptosomal membrane fractions at postnatal days 8 and 14. ¹²⁵I-GVIA binding displacement curves were obtained by incubating membranes with increasing concentrations of unlabeled GVIA, MVIIA, and RVIA. Displacement curves and IC₅₀ were calculated for each of these three ω-conotoxins, and then compared. At PND 14, GVIA, MVIIA and RVIA were able to displace greater than 95% of ¹²⁵I-GVIA binding. At PND 8, however, MVIIA was only able to displace 83% of ¹²⁵I-GVIA binding, and RVIA was only able to block 84%. The IC₁₅₀ does not appear to change significantly during this period of development for any of the ω-conotoxins. The inability of MVIIA and RVIA to completely block ¹²⁵I-GVIA binding in pre-critical period Swiss Webster cortex denotes an alteration in the composition of N-type VSCC binding sites. With this data, we have suggested the presence of subtypes of the N-type VSCC in the cortex of pre-critical period Swiss Webster mouse.