Effects of traditional versus delayed resuscitation on serum lactate and base deficit

OBJECTIVE

To test the hypothesis that delayed resuscitation of hemorrhagic shock produces a less severe shock insult than traditional resuscitation, characterized by repeated episodes of alternating hypotension and normotension.

METHODS

Female pigs were divided into three groups. Sham operated controls (C) (n = 4), sustained hypotension (SS) (n = 6), and hypotension with multiple cycles of shock and resuscitation (SR) (n = 6). SS and SR animals were bled to a mean arterial pressure (MAP) of 50 mmHg. SS animals were maintained at an MAP of 50 mmHg for 65 min and then resuscitated to baseline blood pressure with normal saline and shed blood. SR animals were initially bled and maintained at an MAP of 50 mmHg for 35 min, resuscitated to baseline BP, and subsequently bled and resuscitated twice more. The total period of shock was the same in both SS and SR.

RESULTS

Following hemorrhage, there was a significant increase in lactate and base deficit in SS as compared to C and SR.

CONCLUSION

Delayed resuscitation produces a more profound shock insult than traditional resuscitation.

SHORT COMMUNICATION maternal thyroid dysfunction and c- fos and c- jun expression in rat placenta

Maternal thyroid dysfunction is associated with perturbed fetal brain development and neurological deficits in adulthood in rat and human. To investigate whether these effects occur secondary to placental dysfunction, c- fos and c- jun expression in placenta from normal (euthyroid) and moderately hypothyroid rat dams were investigated by Northern hybridization analysis. In normal placenta, c- fos expression increased by 74 per cent between 16 and 21 days of gestation (dg) whereas c- jun expression declined by 46 per cent. Moderate maternal hypothyroidism depressed placental c- fos expression by 32 per cent at 19 dg, but elevated c- fos and c- jun expression by 139 and 86 per cent, respectively, at 21 dg. Maternal hypothyroidism may therefore induce c- fos/c- jun -related placental dysfunction, but only relatively late in gestation when fetal thyroid function is already established.

Upper extremity stress fractures in athletes: clinical features of 44 cases

PURPOSE

To review the clinical features of a large series of active patients with a stress fracture in a non-weight-bearing location of the upper extremity or ribs.

DESIGN

Multicenter cross-sectional study.

SETTING

Multiple academic medical centers.

PARTICIPANTS

44 patients with a diagnosis of upper extremity or rib stress fracture.

MAIN OUTCOME MEASURES

Clinical features according to anatomic location, primary sport, and subdivided according to the nature of the sport-specific skills involved.

RESULTS

A diagnosis of stress fracture was made in 44 patients based on history and physical examination, and confirmed by radiography, scintigraphy, magnetic resonance imaging (MRI), computed tomography (CT), or a combination of imaging techniques. Patients were subjectively divided into four categories based on the predominant type of upper extremity activity required for participation in their sport: 1) weight lifter (e.g., football, weight lifting, wrestling); 2) upper extremity weight bearer (e.g., gymnastics, diving, cheerleading); 3) thrower (e.g., pitcher, soccer goalie, javelin); or 4) swinger (e.g., golf, tennis). We noted that all fractures in the weight bearers occurred distal to the elbow, whereas in the throwers most fractures affected the shoulder girdle. Lower rib stress fractures predominated in the swingers group, whereas weight lifters had fractures located throughout the upper extremity.

CONCLUSION

Stress fracture should be considered in the differential diagnosis of athletes presenting with upper extremity or rib pain of bony origin that is of insidious onset. Further study of the sport-specific patterns of injury described here may improve our ability to treat and prevent these injuries.

Effect of upregulation of AMPA glutamate receptors on cerebral O(2) consumption and blood flow in rat

AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate) receptors, in cerebral cortex, underwent upregulation (35% increase) following chronic blockade with a non-competitive AMPA receptor antagonist, GYKI 52466 (1-(aminophenyl)-4-methyl-7, 8-methylenedioxy-5H-2,3-benzodiazepine). Such upregulation did not alter basal cerebrocortical blood flow or O(2) consumption. There was a much higher increase in blood flow and O(2) consumption in the upregulated, agonist (AMPA) stimulated cortices of anesthetized rats.

Maternal hypothyroxinemia disrupts neurotransmitter metabolic enzymes in developing brain

Maternal thyroid status influences early brain development and, consequently, cognitive and motor function in humans and rats. The biochemical targets of maternal thyroid hormone (TH) action in fetal brain remain poorly defined. A partially thyroidectomized rat dam model was therefore used to investigate the influence of maternal hypothyroxinemia on the specific activities of cholinergic and monoaminergic neurotransmitter metabolic enzymes in the developing brain. Maternal hypothyroxinemia was associated with reduced monoamine oxidase (MAO) activity in fetal whole brain at 16 and 19 days gestation (dg). A similar trend was observed for choline acetyltransferase (ChAT) activity. In contrast, DOPA decarboxylase (DDC) activity was markedly elevated at 21 dg. Further study of these enzymes at 14 dg showed no differences between normal and experimental progeny - suggesting they become TH sensitive after this age. Tyrosine hydroxylase (TyrH) and acetylcholinesterase (AChE) activities were unaffected prenatally. During postnatal development, the activities of TyrH, MAO, DDC and, to a lesser extent, AChE were increased in a brain region- and age-specific manner in experimental progeny. The prenatal disturbances noted in this study may have wide-ranging consequences since they occur when neurotransmitters have putative neurotropic roles in brain development. Furthermore, the chronic disturbances in enzyme activity observed during postnatal life may affect neurotransmission, thereby contributing to the behavioural dysfunction seen in adult progeny of hypothyroxinemic dams.

The effects of erythromycin on the electrocardiogram

BACKGROUND

Various cardiac electrophysiologic effects have been attributed to erythromycin. During the course of treating a pneumonia patient with IV erythromycin, the conversion of atrial fibrillation to a sinus rhythm, and its subsequent reversal, appeared to be causally related to the introduction and cessation of this antibiotic.

OBJECTIVE

This observation suggested the need for studying the changes in the ECG following the use of IV erythromycin in a typical clinical setting.

DESIGN

A prospective comparative drug study.

SETTING

A university-affiliated teaching hospital.

PATIENTS

Nineteen patients being treated for uncomplicated community-acquired pneumonia.

INTERVENTION

IV erythromycin, 500 mg, and/or IV cefuroxime, 750 mg, infused in 250 mL of saline over 20 min. In the 11 patients who were receiving both of the antibiotics, cefuroxime was administered immediately before erythromycin was infused.

MEASUREMENTS

The 12-lead ECG measurements were obtained before infusion, at 5-min intervals during each infusion, and at 5 and 10 min after the infusions had been completed. All of the ECG complexes and intervals were measured using a software program (Interpretive Cardiograph; Hewlett Packard; Palo Alto, CA).

RESULTS

The administration of IV erythromycin increased heart rate and prolonged the corrected QT (QTc) interval. These changes were significant at 15 min of the infusion, and were no longer evident 5 min after the infusion had been stopped. The administration of IV cefuroxime did not produce any ECG changes.

CONCLUSIONS

A single, standard dose of IV erythromycin prolongs the QTc interval; therefore, the drug should always be administered as a slow infusion. ECG monitoring should accompany erythromycin therapy in critically ill patients, in patients with electrolyte disorders, or in patients taking other drugs with similar cardiac effects.

Superior orbital fissure syndrome in a latent type 2 diabetic patient

Although isolated cranial nerve palsies are common in diabetic patients, multiple, simultaneous cranial neuropathies are rare. We describe the second case of a complete superior orbital fissure syndrome including the optic nerve in a middle-aged Papuan man with newly diagnosed diabetes mellitus. The differential diagnosis included septic cavernous sinus thrombosis and Tolosa Hunt syndrome, and management was initially directed at excluding these serious, treatable conditions.

Neonatal resuscitation--a practical assessment

Current European neonatal resuscitation guidelines (Zideman et al. Resuscitation 1998;37:103-110) advocate cardiopulmonary resuscitation (CPR) at 120 compressions per minute in a ratio of 3:1. This is commonly interpreted as a net rate, thus requiring delivery of 40 breaths per minute, which is the upper end of the range of 30-40 breaths per minute suggested in the guidelines. At least one other interpretation is available, but the correct one is not specified. No studies have evaluated whether the rates inferred by the guidelines can be achieved. This study assesses the ability of trained hospital providers to fulfil these criteria in a simulated arrest scenario. A group of anaesthetists, paediatricians, midwives and neonatal nurses was asked to perform CPR either as single rescuers or in pairs, for 5 min, following European Resuscitation Council guidelines. Breaths and compressions delivered were measured by inductance plethysmography. The number of breaths delivered in the first and fifth minute of the scenario were measured, as well as the quality of delivered breaths. Of 33 single resuscitators, none were able to deliver 40 breaths per minute in either the first minute (range 11-34; median 20; interquartile range 14-26) or the fifth (13-35; 19; 15.25-26.5). Of 18 pairs of rescuers, four achieved 40 breaths per minute in the first minute (24-45; 33.5; 29.75-38.25) but only three of 17 were able to sustain this to the fifth minute (21-48; 35; 30.5 39). One pair did not complete 5 min of resuscitation. Single rescuers were unable to achieve the rate of CPR suggested by current guidelines. Only 22% of paired rescuers were able to achieve this standard in the first minute, falling to less than 20% by the fifth minute. We recommend modifying the guidelines to make them unambiguous and practicable, with the emphasis shifted onto the quality of compressions and ventilations, rather than quantity.

Essential histidyl residues at the active site(s) of sucrose-phosphate synthase from Prosopis juliflora

Chemical modification of sucrose-phosphate synthase (EC 2.4.1.14) from Prosopis juliflora by diethyl pyrocarbonate (DEP) and photo-oxidation in the presence of rose bengal (RB) which modify the histidyl residues of the protein resulted in the inactivation of the enzyme activity. This inactivation was dependent on the concentration of the modifying reagent and the time of incubation and followed pseudo-first order kinetics. For both the reagents, the inactivation was maximum at pH 7.5, which is consistent with the involvement and presence of histidine residues at the active site of the enzyme. Substrates, UDPG and F6P protected the enzyme against the inactivation by the modifying reagents suggesting that the histidine residues may be involved in the binding of these substrates and are essential for the catalytic activity. Specificity of DEP was indicated by an increase in absorbance at 240 nm along with concomitant inactivation of the enzyme and reactivation of the modified enzyme by hydroxylamine. These results strongly suggest the presence of histidine residue(s) at or near the active site of the enzyme.

A comparison of ketorolac tromethamine/oxycodone versus patient-controlled analgesia with morphine in anterior cruciate ligament reconstruction patients

Effective postoperative analgesia with minimal side effects remains an important goal in enabling increasingly complex surgical procedures to be performed on an outpatient basis. In this study, we examined the efficacy of postoperative analgesia in 90 patients undergoing anterior cruciate ligament reconstruction using a patellar tendon autograft, with a 24-hour hospital stay. Patients were randomized to receive either intramuscular ketorolac supplemented by oral oxycodone, or intravenous morphine via patient-controlled analgesia (PCA) device, for postoperative analgesia. Patients were monitored for 2 hours in the recovery room, then every 4 hours until discharge, for the presence of complications of nausea, vomiting, urinary retention, pruritus, and dizziness. Pain was assessed using a visual analog scale (VAS) on the morning of postoperative day one. All patients were discharged by 24 hours after surgery. Ten (20%) of the patients receiving ketorolac/oxycodone versus 31 (79%) of those receiving PCA morphine experienced postoperative complications (P < .05). Postoperative nausea, vomiting, and urinary retention were each significantly more common in the PCA morphine group (P < .05). The incidence of pruritus and dizziness was low overall. There was no significant difference between groups in the severity of postoperative pain as assessed using a VAS. We conclude that ketorolac/oxycodone may provide comparable analgesia with fewer undesirable side effects than PCA morphine in patients undergoing anterior cruciate ligament reconstruction. Patients receiving ketorolac/oxymorphone may have a better quality recovery and more rapid discharge.

Epidermoid cyst of the brain stem : a case report

Intracranial epidermoids account for 0.2 to 1.8 of all brain tumours. We report an epidermoid cyst in an unusual location - the brain stem. At this site safe and adequate resection implies decompression of the cyst contents and removal of the non-adherent cyst capsule.

Transient cerebellar mutism after evacuation of a spontaneous vermian haematoma

Cerebellar mutism after surgery for posterior fossa tumours in children is a well-described, though rare, entity. Most of these tumours are located in the region of the cerebellar vermis extending to the hemispheres. The authors report a case of cerebellar mutism in an 8-year-old boy who underwent surgical evacuation of a spontaneous vermian haematoma. We feel that his mutism was an extreme form of cerebellar dysarthria.

Medullomyoblastoma. A rare cerebellar tumour in children

Seven patients between the ages of 3 and 24 years were admitted to our hospital in the last 28 years who had a histological diagnosis of medullomyoblastoma. These patients presented with classic symptoms of a posterior fossa midline mass associated with evidence of raised ICP. A CT scan in each patient revealed a uniformly high-attenuating tumour in the posterior fossa with gross hydrocephalus. In all seven patients a ventriculoperitoneal shunt was placed prior to definitive surgery. Radical tumour excision was carried out in all cases 3-5 days after CSF diversion. The histological diagnosis was made on H&E-stained slides. In two cases each, the tumour tissue was subjected to electron microscopy and immunohistochemical studies. Six of the seven patients survived the operation. One patient died 21 days after surgery as a result of shunt block and shunt infection. All surviving patients received cranial and spinal radiation 2-4 weeks after surgery, and also chemotherapy. The cranial radiation dose ranged from 4500 to 5000 rad, while the spinal radiation dose was limited to 1500 rad. Patients were followed up carefully. Three patients died within 6 months, and the remaining three between 2.5 and 3 years after surgery. None of the patients in our study survived longer than 3 years. One patient had developed paraplegia. This study highlights the details of an uncommon entity and reports the largest collection of such cases in the literature.

Release of interleukin-2 induced by a major antigenic outer membrane protein of Shigella dysenteriae type 1 in natural infection

An antigen specific modulation of peripheral blood lymphocyte function was examined in a patient-based study of Shigella dysenteriae type 1 infection. Interleukin-2 (IL-2) production by the peripheral blood mononuclear cells (PBMC) from Shigella-infected patients was correlated with the expression of host cellular immune responses. To evaluate the role of a 57 kD major antigenic outer membrane protein of S. dysenteriae 1 in the proliferation of PBMC and the production of IL-2, the in vitro blastogenic transformation assay was employed. The magnitude of the response was monitored morphologically as well as by the proliferation of the IL-2 dependent CTLL-2 cell line. The proliferation of the IL-2 dependent CTLL-2 cell line against PBMC culture fluids after exposure to the major antigen reflected the participation of functionally active T-lymphocytes in shigellosis patients. The precise quantitation of IL-2 concentration in such lymphocyte culture supernatants by immunoassay showed substantial production of IL-2.

Ortner's syndrome revisited

Hoarseness of voice due to paralysis of the left recurrent laryngeal nerve caused by a dilated left atrium in mitral stenosis as discussed by Ortner, is a subject of controversy. Different authors have cited different mechanisms as explanation. A variety of cardiac problems such as primary pulmonary hypertension, ischaemic heart disease, various congenital heart disorders can all lead to paralysis of the left recurrent laryngeal nerve. Most authors believe that pressure in the pulmonary artery causes the nerve compression. In Papua New Guinea cor pulmonale and rheumatic heart disease are the commonest cardiac disorders seen. Ortner's syndrome is a rarity and has never been reported from here before. Here three different case reports are presented with mitral stenosis, primary pulmonary hypertension and combined mitral stenosis and regurgitation and the pathogenesis of hoarseness is discussed.

Primary osteosarcoma of the anterior skull base

Primary skull base osteosarcoma is extremely rare and has been reported mainly in the second decade of life. Two cases of primary osteosarcoma arising from the anterior cranial fossa have been described. Both these patients were in their fifth decades of life.

Binding of Escherichia coli heat-stable enterotoxin and rise of cyclic GMP in COLO 205 human colonic carcinoma cells

Escherichia coli heat-stable enterotoxin (STa) was found to bind on the surface of human colonic (COLO 205) cells. The binding of [125I]STa to cell membranes was found to be specific, reversible and saturable. Scatchard analysis of the equilibrium binding demonstrated a single class of binding sites with a Kd of 0.5 x 10(-10) M. Autoradiographic analysis of polyacrylamide gel electrophoresis revealed the specific incorporation of [125I]STa into a single STa binding protein with a molecular mass of 95 kDa. Following incubation of COLO 205 cells with STa, a rise of intracellular cGMP was also evident.

Trigeminal neurinoma with an apoplectic onset

Intratumoural bleeding into a trigeminal neurinoma is rare. The authors describe a case which had an apoplectic presentation with subsequent persistent unilateral ptosis, hemifacial pain and sensory loss. This proved to be due to a haemorrhage into a large trigeminal neurinoma.

Sucrose-phosphate synthase in tree species: light/dark regulation involves a component of protein turnover in Prosopis juliflora (SW DC)

Light dependent modulation of sucrose-phosphate synthase activity (SPS; EC 2.4.1.14) was studied in a tree species, namely Prosopis juliflora. In this paper we demonstrate that cycloheximide, an inhibitor of cytoplasmic protein synthesis, when fed to detached leaves of P. juliflora through transpiration stream in the dark or in light completely prevents in vivo light activation of Vlim and Vmax activities of SPS. In case of spinach, however, cycloheximide feeding affects only Vlim activity while Vmax activity remained unchanged. In contrast, chloramphenicol, an inhibitor of protein synthesis in chloroplast has no effect on the light activation of SPS in Prosopis. The treatment with cycloheximide showed slight reduction in the rate of O2 evolution indicating that cycloheximide had very little effect on overall photosynthesis. These results indicate that short term protein turnover of the SPS protein and some other essential component(s) (e.g., a putative protein that modifies SPS activity) is one of the primary steps in a complex and unique regulatory cascade effecting the reversible light activation of SPS.

Demonstration of a novel circulating anti-prostacyclin receptor antibody

Although coronary artery disease (CAD) is appreciated to be accelerated in patients with chronic spinal cord injury (SCI), the underlying mechanism of CAD in SCI remains obscure. We have recently shown that platelets from subjects with SCI develop resistance to the inhibitory effect of prostacyclin (PGI2) on the platelet stimulation of thrombin generation. The loss of the inhibitory effect was due to the loss of high-affinity prostanoid receptors, which may contribute to atherogenesis in SCI. Incubation of normal, non-SCI platelets in SCI plasma (n = 12) also resulted in the loss of high-affinity binding of PGI2 (Kd1 = 9.1 +/- 2.0 nM; n1 = 170 +/- 32 sites per cell vs. Kd1 = 7.2 +/- 1.1 nM; n1 = 23 +/- 8 sites per cell), with no significant change in the low-affinity receptors (Kd2 = 1.9 +/- 0.1 microM; n2 = 1,832 +/- 232 sites per cell vs. Kd2 = 1. 6 +/- 0.1 microM; n2 = 1,740 +/- 161 sites per cell) as determined by Scatchard analysis of the binding of [3H]PGE1. The loss of high-affinity PGI2 binding led to the failure of PGI2 to inhibit the platelet-stimulated thrombin generation. The increase of cellular cyclic AMP level, mediated through the binding of PGI2 to low-affinity receptors in platelets, was unaffected in SCI platelets. PAGE and immunoblot of SCI plasma showed the presence of an IgG band, which specifically blocked the binding of [3H]PGE1 to the high-affinity PGI2 receptors of normal platelets. PAGE of the reduced IgG band, the amino acid sequence of the novel band as a heavy chain of IgG that inhibits the binding of [3H]PGE1 to the high-affinity platelet PGI2 receptor, demonstrates that the specific recognition and inhibition of high-affinity PGI2 binding to platelets was due to an anti-prostacyclin receptor antibody present in SCI plasma.

The management of spinal metastasis in children

OBJECTIVE

To seek an optimal treatment plan from the results of treatment for metastatic disease of the spine in children.

DESIGN

An 8-year retrospective study of children with metastatic disease of the spine. Imaging studies were reviewed and treatment modalities analysed.

SETTING

The divisions of pediatric orthopedics and pediatric neurosurgery at the Children's Hospital of Eastern Ontario, Ottawa.

PATIENTS

All children seen between April 1980 and December 1987 who had lesions metastatic to the spine by hematogenous or direct extension. There were 20 children (15 boys, 5 girls) with a mean age at the time of diagnosis of 9.5 years. Follow-up ranged from 2 weeks to 108 months. One child was lost to follow-up.

INTERVENTIONS

Eleven children underwent laminectomy and decompression. Of the 14 neurologically compromised children, 5 received chemotherapy and radiotherapy and 9 received chemotherapy, radiotherapy and surgery.

MAIN OUTCOME MEASURES

Type of metastatic lesion, vertebrae involved and response to therapy.

RESULTS

Vertebrae involved with metastases were as follows: cervical (3), thoracic (5), lumbar (8) and multilevel (2). Meninges were involved in 2 cases. The most common causes of metastatic spinal involvement were neuroblastoma (4 cases) and astrocytoma (6 cases). Pathologic fractures occurred in 4 children and kyphoscoliosis in 4. Spinal cord paresis developed in 14 of the 20 children. Of the 6 children who survived from 48 to 108 months, 5 had tumours of neural origin, 4 being astrocytomas. Children with neuroblastoma or leukemic infiltration had a good initial response to chemotherapy. Five of the 6 surviving children had astrocytomas, and 5 were treated by surgical decompression.

CONCLUSIONS

Metastatic disease of the spine in children secondary to astrocytoma should be treated aggressively, but from the experience gained from this study it is impossible to devise a rigid treatment plan for each type of metastatic tumour. The choice of chemotherapy, radiotherapy or surgery depends on the type of tumour, the age of the child and whether or not the spinal cord is compromised.

Effects of excitatory amino acids on cerebral oxygen consumption and blood flow in rat

This investigation tested the importance of excitatory amino acids' effects on regional cerebral O2 consumption and the concomitant changes in cerebral blood flow (rCBF) in isoflurane anesthetized rats. In the glutamate or N-methyl-D-aspartate (NMDA) groups, 10(-2) M glutamate or NMDA was topically applied to the right cortex and the left cortex was used as a control. One mg/kg dizocilpine maleate (MK-801), a non-competitive NMDA receptor antagonist, was administered (iv) to the MK-801 group and saline was given to the control group. Cortical rCBF was determined using 14C-iodoantipyrine and regional O2 extraction was measured microspectrophotometrically. Cerebral O2 consumption increased 77% after glutamate (contralateral cortex: 9.0 +/- 1.1 ml O2/min/100 g, glutamate treated cortex: 15.9 +/- 3.9), while a 46% increase was observed with the same concentration of NMDA (contralateral cortex: 9.8 +/- 2.0, NMDA treated cortex: 14.3 +/- 5.5). After MK-801, the O2 consumption decreased to 37% of the control value (control cortex: 7.0 +/- 1.3, MK-801 treated cortex: 2.6 +/- 3.9). MK-801 significantly decreased cerebral O2 extraction from 7.1 +/- 1.3 ml O2/100 ml (control cortex) to 5.3 +/- 0.6 (MK-801 treated cortex). However, there was no significant difference in cerebral O2 extraction between treated and contralateral cortex in either the glutamate or NMDA groups. The increase in O2 consumption caused by glutamate or NMDA was coupled with increased rCBF. Glutamate increased rCBF from 95 +/- 5 ml/min/100 g (contralateral cortex) to 165 +/- 31 (treated cortex), while NMDA increased rCBF from 114 +/- 12 (contralateral cortex) to 178 +/- 60 (treated cortex). MK-801 decreased O2 consumption with a lesser decrease of rCBF. The rCBF was 48 +/- 9 in the MK-801 treated cortex and 99 +/- 22 in the control cortex. Some substances produced by the activation of NMDA receptors may be related to the coupling of cerebral metabolism and blood flow, since after blockade of NMDA receptors with MK-801, this relationship is uncoupled. These findings suggest that glutamatergic processes have a major effect on cerebral O2 consumption and that this is at least partly due to NMDA receptors.

An immunological study of vitiligo

Estimation of peripheral T lymphocytes T3, T4, T8 and NK cells was carried out in 30 cases of different clinical types of vitiligo by direct immunofluorescence technique. The cases were divided into two broad groups (1) Localised; and (2) Generalised. These cases were again divided into 3 groups as per duration of disease. Thirty healthy subjects served as control. Decrease in T3 and T4 and increase in T8 with decrease of T4/T8 ratio was seen in both localised and generalised variety. But the T4/T8 ratio was decreased to a greater extent in generalised variety. The NK cells showed significant increase in the generalised variety. As per disease T4/T8 ratio was reduced maximally in patients with disease duration less than one year. Of the generalised category NK cells were increased more in patients having disease duration more than 1 year.

Erythrophagocytosis and its relation to band 3 clustering in chronic myelogenous leukemia

Band 3, a major erythrocyte membrane glycoprotein, undergoes topographic redistribution leading to enhanced clustering, in chronic myelogenous leukemia (CML). This is probably due to the binding of heme compounds to the CML erythrocyte membrane resulting from depletion of cellular levels of reduced glutathione (GSH). Band 3 clustering appears to be one of the factors associated with increased erythrophagocytosis in CML.

Effect of up-regulation of NMDA receptors on cerebral O2 consumption and blood flow in rat

We tested the hypothesis that cerebrocortical blood flow and O2 consumption would be proportional to an up-regulated number of functional N-methyl-D-aspartate (NMDA) receptors. Previous work had shown a relationship between cerebral metabolism and NMDA receptor activity. We increased the specific binding to NMDA receptors in the cerebral cortex, from 2.2 +/- 0.9 to 4.5 +/- 0.8 (density units) in male Long-Evans rats by daily giving two intraperiotoneal injections (30 mg/kg) of CGS-19755, an NMDA receptor inhibitor, for 7 consecutive days (discontinued for 20 h before experiment). Twelve up-regulated (CGS treated) and 12 control rats were used in this study. Under isoflurane anesthesia and after topical stimulation of the right cerebral cortex with 10(-2) M NMDA, the blood flow (14C-iodoantipyrine method) increased from 98 +/- 11 ml/min/100 g in the unstimulated cortex of the control rats to 161 +/- 37 ml/min/100 g in the stimulated cortex. The unstimulated value for blood flow (95 +/- 7 ml/min/100 g) did not change in the upregulated group but it doubled (194 +/- 69 ml/min/100 g) in the stimulated, upregulated cortex. Similarly, O2 consumption (cryomicrospectrophotometrically determined) in normal rats increased 46%, from 9.3 +/- 1 ml/min/100 g to 13.6 +/- 4 after NMDA stimulation. While in the upregulated animals, O2 consumption increased 103% from 7.9 +/- 0.6 to 16 +/- 6.5 after NMDA stimulation. In conclusion, NMDA receptor upregulation does not alter basal cerebrocortical blood flow or O2 consumption but in the NMDA-stimulated cortex, the blood flow and O2 consumption increase is dependent on the number of NMDA receptors present.

Antibody response to outer membrane proteins in Shigella dysenteriae type 1 infection with special reference to appearance of murine antibodies

In shigellosis, the protective immune mechanism is not well established. The bacterial outer membrane proteins (OMPs) may have a role in the induction of immunity due to their outwardly location. The serum antibody response of S. dysenteriae type 1 infected patients against OMPs was assessed by enzyme linked immunosorbent assay (ELISA). A striking elevation of serum IgG response was noted during the convalescent phase. Murine antiserum directed against S. dysenteriae 1 OMPs was found to be highly cross reactive with the OMPs isolated from heterologous species. A major antigenic OMP was partially purified and showed distinct immunodominance in ELISA. These observations suggest that the specific component may have some immunoprophylactic potential.

Pulmonary capillary pressure during exercise in horses

The object of this study was to relate pulmonary capillary pressure to arterial and wedge pressures during exercise. Pulmonary vascular pressures were measured in six standardbred horses exercising at speeds equivalent to 75, 90, and 100% of maximal heart rate. Vascular pressures were measured with transducer-tip catheters and expressed relative to esophageal pressure. Pulmonary capillary pressure was estimated by the arterial-occlusion technique modified for exercise. Mean pulmonary arterial, capillary and wedge pressures increased from 30.5 +/- 6.3, 17.8 +/- 4.3, and 13.4 +/- 1.6 mmHg, respectively, at rest, to 70.5 +/- 5.2, 42.1 +/- 5.3, and 38.4 +/- 5.6 mmHg, respectively, at maximal exercise. The largest part of the increase occurred during the first level of exertion. With exercise, the pressure across the lung barely doubled at a time when the cardiac output would have increased at least fivefold. Thus the absolute resistance in both pre- and postcapillary segments must have decreased. The capillary and wedge pressures rose similarly, whereas the difference between them did not change with exertion. The fractional resistance of the precapillary segment increased with exercise. The postcapillary resistance, initially 28% of the total pulmonary vascular resistance, fell to 9% at maximal exercise. The rise (to approximately 45 mmHg) in pulmonary capillary pressure with exertion is consistent with an increase in transvascular filtration.

Intestinal infarction in systemic lupus erythematosus--report of a case with an unusual obliterative vascular lesion

Intestinal infarction is a rare complication of systemic lupus erythematosus (SLE). A 26-year-old Papua New Guinean female who developed such a complication and underwent emergency laparotomy is described. The pathological changes in the mesenteric vessels and possible pathogenetic mechanisms are discussed. The relevant literature is briefly reviewed.

Loss of high-affinity prostacyclin receptors in platelets and the lack of prostaglandin-induced inhibition of platelet-stimulated thrombin generation in subjects with spinal cord injury

Coronary artery disease is a leading cause of death in individuals with chronic spinal cord injury (SCI). However, platelets of those with SCI (n = 30) showed neither increased aggregation nor resistance to the antiaggregatory effects of prostacyclin when compared with normal controls (n = 30). Prostanoid-induced cAMP synthesis was similar in both groups. In contrast, prostacyclin, which completely inhibited the platelet-stimulated thrombin generation in normal controls, failed to do so in those with SCI. Scatchard analysis of the binding of [3H]prostaglandin E1, used as a prostacyclin receptor probe, showed the presence of one high-affinity (Kd1 = 8.11 +/- 2.80 nM; n1 = 172 +/- 32 sites per cell) and one low-affinity (Kd2 = 1.01 +/- 0.3 microM; n2 = 1772 +/- 226 sites per cell) prostacyclin receptor in normal platelets. In contrast, the same analysis in subjects with SCI showed significant loss (P < 0.001) of high-affinity receptor sites (Kd1 = 6.34 +/- 1.91 nM; n1 = 43 +/- 10 sites per cell) with no significant change in the low affinity-receptors (Kd2 = 1.22 +/- 0.23; n2 = 1820 +/- 421). Treatment of these platelets with insulin, which has been demonstrated to restore both of the high- and low-affinity prostaglandin receptor numbers to within normal ranges in coronary artery disease, increased high-affinity receptor numbers and restored the prostacyclin effect on thrombin generation. These results demonstrate that the loss of the inhibitory effect of prostacyclin on the stimulation of thrombin generation was due to the loss of platelet high-affinity prostanoid receptors, which may contribute to atherogenesis in individuals with chronic SCI.

Anticlastogenicity of vitamin C in vivo against the cytogenetic toxicity of muriate of potash in murine bone marrow cells

The potential in vivo anticlastogenicity of vitamin C was evaluated in murine bone marrow cells against the cytogenetic toxicity of muriate of potash, a synthetic fertilizer. The animals were treated orally once daily for 7 days with muriate of potash (5g/kg) and/or vitamin C (10mg/kg). Metaphase chromosome analyses revealed that muriate of potash induced chromosomal abnormalities were significantly decreased, though still remained higher to control, when vitamin C was administered concurrently. The possible role of vitamin C in mitigating the muriate of potash induced cytogenetic toxicity is discussed.

Effect of cryoprotectants on release of various enzymes from buck spermatozoa during freezing

Semen samples from 12 bucks Were extended with 10 different extenders containing glycerol, DMSO, glycerol + DMSO, and glycerol + lactose in varying concentrations as cryoprotective agents. The activities of acrosin, hyaluronidase, alkaline phosphatase (AKP), aspartate aminotransferase (AST), alanine amino transferase (ALT) and lactic dehydrogenase (LDH) were assayed in equilibrated (Prefreeze) and frozen thawed (Postfreeze) semen samples. Significantly (P < 0.01) higher intracellular activity of acrosin was recorded in semen samples extended with lactose than with the other extenders, with the maximum being with Tris yolk glycerol lactose (TYGL(180)). Effects of extenders on acrosin activity were significant (P < 0.01) at both of the pre-and postfreeze stages. However, extracellular activities of hyaluronidase, alkaline phosphatase, transaminases (AST and ALT), and lactic dehydrogenase were significantly higher in extenders containing DMSO than lactose. Leakage of these enzymes was found to increase from the prefreeze to the post freeze stage.

Severe motorcycle injury in Mersey region and North Wales

Ninety-three patients were involved in serious motorcycle accidents (death or Injury Severity Score more than 15) during a 1-year period among a total of 554 victims of serious road traffic accidents studied at 16 district general and teaching hospitals. There were 91 males and two females. The average age was 29 years (range 15-81 years). Of these, 32 per cent died at the scene of the accident or in transit; 68 per cent arrived alive at the above hospitals. Of the latter, 30 per cent died in hospital. The commonest cause of death was multiple injuries. The Injury Severity Score of patients admitted to hospital was a mean of 32.1. The Glasgow Coma Score was below 9 in 33.8 per cent. Of those admitted to hospital, the average length of stay was 38.7 days. 67 per cent were admitted to intensive therapy unit of whom 41.3 per cent had to be ventilated for an average of 3.55 days. There were four preventable deaths among the patients who died after being admitted to hospital. Many body areas are frequently injured in motorcycle accidents which occur usually in fit males. Careful assessment along with vigorous and aggressive treatment is particularly important for this group. Access to a specialized trauma centre would be beneficial.

Effect of methylxanthines on motility and fertility of frozen-thawed goat semen

We studied the effects of 2 methylxanthines (caffeine and theophylline) at different concentrations on goat sperm motility and live spermatozoa and on the percentage of acrosomal damage and fertility. Altogether, 144 semen samples collected from 12 bucks (3 each from Black Bengal and Beetal, and 6 from cross-breds) were diluted in TRIS extender, divided into 5 equal fractions; then caffeine and theophylline were added at 2 concentrations (2 and 5 mM) in different fractions. These samples were frozen in liquid nitrogen vapor, thawed at 37 degrees C for 15 sec, and evaluated for motility and other semen attributes. Addition of caffeine and theophylline had a stimulatory effect on goat spermatozoa. It was further observed that the effect of these agents was concentration-dependent, with 2 mM caffeine and 5 mM theophylline yielding the best results in respect to the percentage of motility in all 3 breeds of goats tested. Among the two methylxanthines used, caffeine was found to be the more effective in Improving motility than theophylline. There was no significant effect on the percentages of live spermatozoa and acrosomal damage due to the addition of these 2 methylxanthines to the extender. Fertility rates with Tris + 2 mM caffeine (60.20 %) and with Tris + 5 mM theophylline (58.88 %) extended semen were apparently higher than those with the Tris-diluted semen (50.0 %), although these differences were not significant.

Role of outer membrane proteins on the adherence of Vibrio parahaemolyticus to rabbit intestinal epithelial cell in vitro

Antiserum against outer membrane preparation of a Kanagawa phenomenon-positive strain of Vibrio parahaemolyticus were raised in rabbits and absorbed with their lipopolysaccharide. The anti-outer membrane protein serum and its Fab (IgG) fragment inhibited the adherence of Kanagawa-positive strains to rabbit intestinal epithelial cells in vitro. Preincubation of rabbit intestinal epithelial cells with outer membrane preparation also inhibited the adherence of these bacteria. Anti-lipopolysaccharide serum or its Fab (IgG) fragment did not inhibit adherence of V. parahaemolyticus. Moreover, pre-treatment of rabbit intestinal epithelial cells with lipopolysaccharide did not inhibit adherence of these strains. These results suggest that outer membrane proteins of V. parahaemolyticus play an important role in the adherence of Kanagawa-positive strains to rabbit intestinal epithelial cells.

Special features of coronary heart disease in people of the Indian sub-continent

Contrary to the popular belief, coronary heart disease (CHD) is indeed common in the Indian sub-continent. Expatriate Indians in their newly adopted countries have 3 to 5 times more chance of developing CHD than the native population or the other immigrant groups. The well-known risk factors such as hypercholesterolemia, hypertension and smoking do not appear to play a major role, while the syndrome of insulin resistance seems to be an important risk factor for CHD in people of this sub-continent. Abdominal obesity, hypertriglyceridemia, and low plasma HDL cholesterol are the markers of this syndrome. Increased plasma insulin levels or even better, the C-peptide measurement may help in identifying the abnormality early. As CHD among Indians has been found to be severe and more diffuse with serious complications and increased mortality at a younger age, preventive measures need to be instituted early. Low fat and complex carbohydrate diet along with regular aerobic exercise may help reduce abdominal obesity, improve insulin sensitivity and HDL cholesterol levels. Hypertriglyceridemia uncontrolled by above measures may require pharmacotherapy with agents such as gemfibrozil. Smoking must be stopped to help reduce insulin resistance and improve HDL levels and endothelial function. Those with hypertension should be considered for therapy with ACE inhibitors, which may improve insulin sensitivity. In patients with insulin resistance, therapy with metformin or troglitazone may be helpful.

Effect of cryoprotectants on certain seminal attributes and on the fertility of buck spermatozoa

Semen samples were obtained from 12 bucks (3 Beetal, 3 Black Bengal and 6 Beetal x Black Bengal) and 10 different extenders were constituted with varying concentrations of glycerol, DMSO, glycerol + DMSO and glycerol + lactose as the sperm cryoprotective agents. After the collection of semen samples, they were assessed for quality, diluted in different extenders after removal of seminal plasma, packaged in ministraws and frozen after equilibration (5'C) for 5 h. The samples were evaluated immediately after equilibration and again 24 h after freezing for progressive motility, percentage of live spermatozoa and acrosome, head and tail abnormalities. Both motility and the percentage of live spermatozoa were most affected by extenders containing only DMSO and these values improved in glycerol + DMSO extenders as the concentration of glycerol was increased while DMSO was decreased. However, these values were significantly higher in extenders containing glycerol + lactose as the cryoprotective agents, and were found to increase with increased concentration of lactose, being highest in TYGL (180). Acrosomal and tail abnormalities tended to increase between post equilibration and post thawing stage, and were higher in extenders containing the higher levels of DMSO. Significantly (P < 0.01) lower percentages of abnormalities were recorded in the glycerol + lactose extenders. The fertility results showed nonsignificant effect of extenders on the conception rate of does.

Assessment of long-term glycaemic control in diabetic patients attending Port Moresby General Hospital

Good glycaemic control is important in preventing the acute and long-term complications of diabetes mellitus. We assessed long-term glycaemic control using glycosylated haemoglobins in 83 diabetic patients, of mean age 47 years and of mean known duration 4.5 years, attending Port Moresby General Hospital over a one-year period. Significant improvement in glycaemic control was observed in only 11 (13%) of the patients. Glycaemic control worsened in 13 (16%) and no change was observed in the remainder (71%). Mean glycosylated haemoglobin and fasting plasma glucose levels were similar at the beginning and end of the study period. Over a one-year period 53 patients (64%) exhibited poor control with mean glycosylated haemoglobin levels exceeding 10%. Among the 19 newly diagnosed diabetic patients (23% of the total) glycaemic control improved in only 2 (11%). Glycaemic control was not influenced by sex, treatment, obesity or duration of diabetes. The demonstration of poor metabolic control in the majority of patients suggests that urgent measures are needed to reevaluate the management of diabetic patients, particularly with respect to education and diet. This may improve the poor survival rates reported in diabetic patients from Papua New Guinea.

Effect of cigarette smoking on lipid profile in the young

In view of the controversies existing regarding the atherogenic potential of smoking, this study was conducted in 40 healthy young male Cigarette smokers and 40 age and weight matched male non smokers, to find out the difference in the serum lipid profiles of both the groups. Subjects in both the groups were in the age range of 25 and 35 years having no history of alcohol abuse or diseases like diabetes mellitus or obesity. The mean serum total cholesterol (177.3 +/- 32.5 mg/dL) and LDL cholesterol (100.2 +/- 31.0 mg/dL) were significantly higher in smokers (p < 0.05) whereas mean serum HDL- Cholesterol was (43.2 +/- 5.8 mg/dL) was significantly lower (P < 0.05). Mean triglyceride (170.8 +/- 59.7 mg/dL) was significantly higher in smokers than in nonsmokers (p < 0.01). In the fed state the total serum cholesterol level and triglyceride level was increased by 10.4 mg/dL and 51.1 mg/dL respectively in smokers whereas the increase was 4.8 mg/dL and 24.3 mg/dL respectively in nonsmokers. There was less rise of HDL cholesterol (1.9 mg/dL) in smokers as compared to that in nonsmokers (3.4 mg/dL) and in LDL-cholesterol (1.8 mg/dL) in smokers compared to nonsmokers (3.4 mg/dL) in fed state.

Electrophysiological studies in children with paralytic poliomyelitis

H-reflex latency (H-RL) and H/M ratio were measured in normal children and children with paralytic poliomyelitis of 1-3 years of age. The H-RL was considerably increased in both the involved and uninvolved limbs of the patients, whereas the H/M ratio did not differ. The Mmax value in the involved limb was very low, and therefore, a corrected H/M ratio was calculated for that side only. The corrected H/M ratio was significantly less than the H/M ratio observed in the uninvolved and control limbs. The distal motor latency was also increased in the involved side.

Insulin-induced release of plasminogen activator from human blood platelets

Incubation of washed platelets in Tyrode buffer, pH 7.5, with insulin (200 microU/ml) and CaCl2 (1.2 mM) at 37 degrees C for 3 h resulted in a threefold increase of plasminogen activator activity in the supernatant over the basal level as determined by both the amidolytic assay and the proteolysis of alpha-casein through the formation of plasmin from plasminogen. This plasminogen activator showed no plasmin-like activity and was inhibited by anti-tissue plasminogen activator antibody as well as by type 1 plasminogen activator inhibitor. The substrate specificity and the inhibition of the enzymic activity by various inhibitors indicated that the platelet plasminogen activator (pPA) was related to tissue-type plasminogen activator of relative molecular weight 56,000. Fibrinolytic activity of pPA and its insulin-dependent release were demonstrated by the shortening of euglobulin lysis time and by the clot lysis time of platelet-rich plasma from normal and type I diabetes mellitus patients. Treatment of platelet membranes with insulin also increased the release of pPA. Increased levels of adenosine 3',5'-cyclic monophosphate (cAMP) in platelets by incubation with various agents completely inhibited the insulin-induced release of the activator. On the other hand, inhibition of platelet aggregation by aspirin had no effect on the release of pPA, indicating that the effect of cAMP was not due to the inhibition of platelet aggregation by the nucleotide.