Hepatic sickling crisis mimicking recurrent cholangitis

A 22-year-old man with homozygous sickle cell disease presented with recurrent fever, right upper quadrant pain and jaundice. Liver biopsy confirmed the diagnosis of hepatic sickling crisis; the symptoms responded to hydroxyurea therapy. Hepatic vasocclusive crisis can diagnosed on liver biopsy, and need not be a diagnosis of exclusion.

Akt-dependent potentiation of L channels by insulin-like growth factor-1 is required for neuronal survival

The insulin-like growth factor-1 (IGF-1)/receptor tyrosine kinase recently has been shown to mediate neuronal survival and potentiate the activity of specific calcium channel subtypes; survival requires Akt, a serine/threonine kinase. We demonstrate here that Akt mediates the IGF-1-induced potentiation of L channel currents, but not that of N channels. Transient expression of wild-type, dominant-negative, and constitutively active forms of Akt in cerebellar granule neurons causes, respectively, no change in IGF-1/L channel potentiation, complete inhibition of potentiation, and a dramatic increase in basal L currents accompanied by the loss of ability to induce further increases. In no case is the IGF-1 potentiation of N currents affected. We additionally find that IGF-1 partially mediates granule neuron survival via L channel activity and that Akt-dependent L channel modulation is a necessary component. Interestingly, very brief exposure (1 min) to IGF-1 triggers nearly complete survival and requires L channel activity. These results strongly suggest that neuronal receptor tyrosine kinases can control long-term calcium-dependent processes via the rapid control of voltage-sensitive channels.

Leg symptoms, the ankle-brachial index, and walking ability in patients with peripheral arterial disease

OBJECTIVE

To determine how functional status and walking ability are related to both severity of lower extremity peripheral arterial disease (PAD) and PAD-related leg symptoms.

DESIGN

Cross-sectional study.

SETTING

Academic medical center.

PARTICIPANTS

Patients aged 55 years and older diagnosed with PAD in a blood flow laboratory or general medicine practice (n = 147). Randomly selected control patients without PAD were identified in a general medicine practice (n = 67).

MEASUREMENTS

Severity of PAD was measured with the ankle-brachial index (ABI). All patients were categorized according to whether they had (1) no exertional leg symptoms; (2) classic intermittent claudication; (3) exertional leg symptoms that also begin at rest (pain at rest), or (4) exertional leg symptoms other than intermittent claudication or pain at rest (atypical exertional leg symptoms). Participants completed the 36-Item Short-Form Health Survey (SF-36) and the Walking Impairment Questionnaire (WIQ). The WIQ quantifies patient-reported walking speed, walking distance, and stair-climbing ability, respectively, on a scale of 0 to 100 (100 = best).

MAIN RESULTS

In multivariate analyses patients with atypical exertional leg symptoms, intermittent claudication, and pain at rest, respectively, had progressively poorer scores for walking distance, walking speed, and stair climbing. The ABI was measurably and independently associated with walking distance (regression coefficient = 2.87/0.1 ABI unit, p =.002) and walking speed (regression coefficient = 2.09/0.1 ABI unit, p =.015) scores. Among PAD patients only, pain at rest was associated independently with all WIQ scores and six SF-36 domains, while ABI was an independent predictor of WIQ distance score.

CONCLUSIONS

Both PAD-related leg symptoms and ABI predict patient-perceived walking ability in PAD.

Exertional leg symptoms other than intermittent claudication are common in peripheral arterial disease

BACKGROUND

Epidemiological data show that most community-dwelling men and women with lower-extremity peripheral arterial disease (PAD) do not have typical symptoms of intermittent claudication. We compared the prevalence of intermittent claudication, leg symptoms other than intermittent claudication, and absence of exertional leg symptoms between patients with PAD identified from a blood flow laboratory (group 1), patients with PAD in a general medicine practice (group 2), and control patients without PAD (group 3).

METHODS

Numbers of participants in groups 1, 2, and 3 were 137, 26, and 105, respectively. Patients with previously diagnosed PAD were excluded from groups 2 and 3. All participants underwent ankle-brachial index measurement and were administered the San Diego claudication questionnaire to assess leg symptoms.

RESULTS

Within groups 1, 2, and 3, prevalences of intermittent claudication were 28.5% (n = 39), 3.8% (n = 1), and 3.8% (n= 4), respectively. Prevalences of exertional leg symptoms other than intermittent claudication were 56.2% (n= 77), 42.3% (n= 11), and 19.0% (n = 20), respectively. Absence of exertional leg symptoms was reported by 15.3% (n= 21), 53.8% (n= 14), and 77.1% (n=81), respectively. Among patients with PAD, older age, male sex, diabetes mellitus, and group 2 vs group 1 status were associated independently with absence of exertional leg symptoms in multivariable regression analysis. Lower ankle-brachial index levels and group 1 vs group 2 status were associated with intermittent claudication.

CONCLUSIONS

Clinical manifestations of PAD are diverse, particularly among patients identified by ankle-brachial index screening. Exertional leg symptoms other than intermittent claudication are common in PAD. Patients with PAD who are older, male, diabetic, or identified with ankle-brachial index screening in a primary care setting are more likely to have asymptomatic PAD.

Porcine endotoxemic shock is associated with increased expired nitric oxide

OBJECTIVES

Nitric oxide (NO) is believed to decrease systemic vascular resistance in sepsis, but the data are mainly from studies on rats and mice. We tested this hypothesis in pigs and also whether there is induction of the inducible form of nitric oxide synthase (iNOS).

DESIGN

Animal study.

SETTING

University center.

SUBJECTS

Ten pigs.

INTERVENTIONS

The pigs were anesthetized and mechanically ventilated.

MEASUREMENTS AND MAIN RESULTS

Pulmonary and systemic hemodynamics were monitored and mixed expired NO was measured by chemiluminescence. Animals received 20 microg/kg of endotoxin over 2 hrs. We then infused 25 mg/kg of N(omega)-nitro-L-arginine methyl ester (L-NAME) over 10 mins, followed by 0.5 g/kg of L-arginine, the precursor of NO, for 30 mins more to reverse the effects of L-NAME. Five additional pigs were treated with 20 microg/kg of endotoxin for 2 hrs and followed for another hour. Plasma nitrite/nitrate was measured by Greiss reaction. The animals were then killed and tissues were sampled for iNOS by Western blot, and iNOS messenger RNA by reverse transcriptase polymerase chain reaction. After endotoxin infusion, arterial pressure (BP) initially increased, then decreased to 62+/-1 mm Hg from the baseline of 115+/-4 mm Hg (p<.001). Cardiac output initially decreased, then increased slightly from the baseline of 3.7+/-0.2 to 4.2 +/-0.3 L/min (p<.05). The BP pattern was mirrored by an increase in expired NO concentration from 6.4+/-0.8 to 10.4+/-1.4 parts per billion (p<.05) and increased rate of pulmonary NO excretion in expired gas (VeNO) from 71+/-10 to 146+/-24 pmol/kg/min (p<.05). Inhibition of NOS with L-NAME decreased expired NO concentration and VeNO and increased BP; however, cardiac output decreased. The vasoconstriction produced by L-NAME was partially reversed by L-arginine, and this also increased VeNO from 80+/-18 after L-NAME to 132+/-31 pmol/kg/min (p<.05). Plasma nitrite (n = 5) did not change and there was no iNOS by Western blot analysis in multiple tissues. However, there was a small increase in messenger RNA by reverse transcriptase polymerase chain reaction.

CONCLUSIONS

The time course and pattern of changes in expired NO during endotoxemia followed the change in systemic hemodynamics, which supports a causal role for NO in sepsis. However, this is not due to a large production of NO by iNOS induction. The hemodynamic pattern, nitrite in blood, and changes in expired NO also differed markedly from those findings in rodent models and caution should be used in extrapolating from rodents to higher order animals.

Autoimmune sclerosing cholangitis: an overlap syndrome in a child

We report an overlap syndrome of autoimmune chronic liver disease and primary sclerosing cholangitis in a young girl. This could be the first such report from India.

Inflammatory bowel disease in children: Indian perspective

The magnitude of inflammatory bowel disease in childhood in India is largely unknown. At the Pediatric Gastroenterology section of PGIMER, Chandigarh, 15 out of 294 children (5%) admitted for colonic disorders were diagnosed to have ulcerative colitis. Diagnosis is suspected on the basis of clinical presentation and established by sigmoidoscopy, rectal biopsy and double contrast barium enema. Widely prevalent bacillary dysentery, acute amoebic colitis and antibiotic induced colitis need to be kept in differential diagnosis of acute presentation of ulcerative colitis. Chronic or recurrent colitis needs to be differentiated from tuberculous colitis. Inflammatory bowel disease deserves clinical suspicion in all unusual cases of colitis which do not respond to treatment of common infective agents.

Repression of enzymes of the pentose phosphate pathway by glucose in fission yeast

We examine here the effect of carbon sources on the synthesis of the shunt pathway enzymes in the fission yeast Schizosaccharomyces pombe growing on a mixture of ethanol and glycerol. Delta-gluconolactone induces practically every one of these enzymes. Glucose in contrast tends to attenuate the synthesis of the majority of them. RNA analysis confirms that their induction and repression reflect changes in the levels of their transcripts.

What do parents know about lead poisoning? The Chicago Lead Knowledge Test. Pediatric Practice Research Group

OBJECTIVES

To examine the extent of parental knowledge about lead poisoning and its prevention and to determine characteristics associated with accurate lead knowledge.

SETTING

Twenty-three pediatric practices and 1 family practice in Chicago, Ill, and its suburbs.

METHODS

A 24-question test regarding lead poisoning and its prevention (Chicago Lead Knowledge Test) was developed based on lead specialists' review and parental test-retest reliability. One point was assigned for each correct response. It was self-administered by a sample of 2225 parents of 0- to 6-year-old children visiting study practices. A 1-way analysis of variance (ANOVA) was used to determine the association of demographic descriptors with test scores.

RESULTS

Respondents had a mean age of 33 years. Ninety percent were mothers, 49% were college graduates, and 80% were home owners. Fifteen percent lived in homes built before 1950, of which 36% were remodeled or renovated during the last 6 months. Respondents' youngest children were 80% white, 10% Hispanic, 5% African American, and 5% other. Ten percent received Medicaid and 86% had other medical insurance. Thirty-four percent recalled receipt of lead information from a health care provider, and 2.4% had had a child with a blood lead level of 0.48 micromol/L (10 microg/dL) or higher. The mean Chicago Lead Knowledge Test score was 12.2 (SD, 3.7). Questions related to lead exposure were more often answered correctly than those related to prevention and diet. In the ANOVA model, those who recalled receipt of lead information from a health care provider, college graduates, respondents aged 30 years or older, Hispanic respondents, and those living in homes built before 1950 had higher scores (all ANOVA P< or =.001).

CONCLUSIONS

Parents do not have much knowledge of ways to prevent childhood lead poisoning. Information from a health care provider can aid parental knowledge. The Chicago Lead Knowledge Test is a new self-administered tool to help evaluate lead education programs.

Characterizing alterations in the pulmonary surfactant system in a rat model of Pseudomonas aeruginosa pneumonia

Bacterial pneumonia remains a significant cause of patient morbidity and mortality worldwide. Pulmonary surfactant serves to maintain homeostasis in the lung through the maintenance of alveolar stability and the regulation of the alveolar immune response. The purpose of this study was to characterize the lung injury and associated surfactant alterations in a rat model of acute Pseudomonas aeruginosa pneumonia. Pneumonia was induced in male Sprague-Dawley rats via intratracheal injection of 0.2 ml, phosphate-buffered saline (PBS) containing P. aeruginosa (6x10(8) colony-forming units x mL(-1)). Control animals received 0.2 mL sterile PBS. Twenty-four hours after inoculation, the pneumonia group (PN) exhibited clinical signs of pneumonia including deficits in gas exchange, leukopenia and elevated arterial lactate levels. Morphological assessment confirmed the presence of pneumonia with airspaces filled with polymorphonuclear cells. Lung homogenate analysis demonstrated evidence of bacterial colonization of pneumonic lung tissue. Lung compliance was also significantly lower in the PN group. Lung lavage analysis of PN rats revealed the pooled surfactant levels to be lower and the surfactant function reduced compared to control rats. Surfactant composition was also found to be altered in PN rats. These results demonstrate that in Pseudomonas aeruginosa pneumonia, the pulmonary surfactant system is both poorly functioning and reduced in quantity. These alterations may contribute to the lung dysfunction characteristic of this disorder.

Regional changes in 5-HT1A but not in 5-HT2A receptors in mouse brain after Semliki Forest virus infection: radioligand binding and autoradiographic studies

Dysfunction of brain 5-hydroxytryptaminergic systems has been associated with several neurological and psychiatric diseases which may have a viral aetiology. The effect of Semliki Forest virus (SFV) on 5-hydroxytryptamine (5-HT1A and 5-HT2A) receptors in mouse brain has been assessed by membrane homogenate binding and autoradiography. Adult mice were injected with saline or virus and brains removed 2, 6, 14, 22 and 35 days after infection. 5-HT1A and 5-HT2A receptors were characterised by saturation studies using [3H] 8-OH-DPAT and [3H] Ketanserin respectively. SFV infection increased 5-HT1A receptor numbers by up to 80% in the cortex on days 6, 14, and 22 but had no effect on Bmax in the midbrain, pons/medulla and the hypothalamus. SFV infection did not affect 5-HT2A receptor number in any of the brain regions studied and the affinity (Kd) of either ligand for 5-HT1A or 5-HT2A receptors was unaffected. Autoradiographic mapping of 5-HT1A receptors in SFV-infected brain showed substantially higher binding in nucleus accumbens, tenia tecta, septohippocampal nucleus, septum, medial and basolateral amygdaloid nucleus, anterioventral preoptic nucleus, hippocampus, interpeduncular nucleus, frontal, lateral orbital, and entorhinal cortex and claustrum on days 6 and 14. Elevated binding persisted in tenia tecta, frontal, lateral orbital, entorhinal cortex, and hippocampal formation to day 22. Autoradiography of 5-HT2A receptors using [3H] Ketanserin showed no difference in the binding in SFV-infected brains. A decrease in plasma corticosterone levels in SFV-infected mice was observed on post infection days 6 and 22. These results show SFV infection induces a regionally selective upregulation of 5-HT1A but not 5-HT2A receptors.

Endogenous pulmonary nitric oxide in the regulation of airway microvascular leak

Endogenous nitric oxide (NO) is an important modulator of airway function, but its role in the regulation of airway microvascular leak (AMVL) remains unclear. Thus we assessed the effects of NO synthase (NOS) inhibition on expired NO (ENO) levels and on AMVL measured by the Evans blue dye technique in guinea pigs. In control unsensitized animals, systemic NG-nitro-L-arginine methyl ester (L-NAME) reduced ENO by 70 +/- 8% (P < 0.01) and reduced AMVL by 92 +/- 1 and 44 +/- 17% (P < 0.05 for both) in the extrapulmonary and intrapulmonary airways, respectively. In animals sensitized and challenged with intratracheal antigen, markedly increased levels of AMVL and ENO were similarly attenuated by L-NAME. In contrast, aminoguanidine, a relatively selective type II NOS inhibitor, reduced ENO in both antigen-sensitized and control unsensitized animals by 39 +/- 3% (P < 0.01) but had no effect on AMVL. These data indicate that endogenous pulmonary NO contributes to both basal and antigen-stimulated levels of AMVL in guinea pigs and that this NO-dependent activity does not appear to be derived from type II NOS.

Primary alpha-sarcoglycan deficiency responsive to immunosuppression over three years

An 8-year-old girl developed weakness over 2 years and an elevated creatine kinase. The biopsy was most consistent with an active dystrophy with many inflammatory cells present. A trial of immunosuppression was started. In the first 2 months of treatment with prednisone, she had functionally and quantitatively significant improvement in her proximal strength. Over 3 years of treatment she maintained stable strength. Subsequent genetic studies showed that she had primary alpha-sarcoglycan deficiency. The timing and the degree of benefit in strength were similar to that seen in boys with Duchenne muscular dystrophy who are treated with prednisone.

The ankle brachial index independently predicts walking velocity and walking endurance in peripheral arterial disease

OBJECTIVES

Maintaining function among older men and women is an important public health goal as the population lives longer with chronic disease. We report the relationships between lower extremity peripheral arterial disease (PAD), PAD severity, and PAD-related symptoms with walking velocity and endurance among men and women aged 55 and older.

DESIGN

A cross-sectional design.

SETTING

An academic medical center.

PARTICIPANTS

Participants with PAD were men and women aged 55 and older identified from a blood flow laboratory or a general medicine practice (n = 158). Randomly selected controls without PAD were identified from the general medicine practice (n = 70).

MEASUREMENTS

PAD was diagnosed and quantified using the ankle brachial index (ABI). Subjects were categorized according to whether they had severe PAD (ABI <0.40), mild to moderate PAD (ABI 0.40 to <0.90), or no PAD (ABI 0.90 to <1.50). Walking endurance was assessed with the 6-minute walk. Usual walking velocity and maximal walking velocity were assessed with "usual" and "maximal" paced 4-meter walks, respectively.

RESULTS

Average distances achieved in the 6-minute walk were 1569+/-390 feet for subjects with ABI 0.90-1.50, 1192+/-368 feet for subjects with ABI 0.40 to <0.90, and 942+/-334 feet for subjects with ABI < 0.40 (trend P value < .001). Walking velocities for both the usual and maximal paced 4-meter walks were slowest among subjects with ABI < 0.40 and fastest among subjects with ABI 0.90 to <1.50. Subjects with PAD who had pain at rest had slower walking velocity and poorer walking endurance than other subjects with PAD. In multiple linear regression analyses that included subjects with PAD only, ABI level was an independent predictor of 6-minute walk performance (regression coefficient = 159 ft/0.40 ABI units, P = .011), usual paced 4-meter walk (regression coefficient = .095 meters/sec/0.40 ABI units, P = .031), and maximal paced 4-meter walk (regression coefficient = .120 meters/sec/0.40 ABI units, P = .050) adjusting for age, sex, race, leg symptoms, and comorbid diseases known to affect functioning. Pain at rest was associated independently with the maximally paced 4-meter walk (-0.201 meters/sec, P = .024), but not with the other walks.

CONCLUSION

ABI level has a measurable and independent association with walking endurance and both usual and maximal walking velocity. These data suggest that PAD may impair lower extremity function by diminishing function of both Type I ("slow twitch") and Type II ("fast twitch") muscle fibers. Because walking velocity has important prognostic implications for functioning, these data also suggest that ABI may be used to identify patients at increased risk of mobility loss.

SAP90 binds and clusters kainate receptors causing incomplete desensitization

The mechanism of kainate receptor targeting and clustering is still unresolved. Here, we demonstrate that members of the SAP90/PSD-95 family colocalize and associate with kainate receptors. SAP90 and SAP102 coimmunoprecipitate with both KA2 and GluR6, but only SAP97 coimmunoprecipitates with GluR6. Similar to NMDA receptors, GluR6 clustering is mediated by the interaction of its C-terminal amino acid sequence, ETMA, with the PDZ1 domain of SAP90. In contrast, the KA2 C-terminal region binds to, and is clustered by, the SH3 and GK domains of SAP90. Finally, we show that SAP90 coexpressed with GluR6 or GluR6/KA2 receptors alters receptor function by reducing desensitization. These studies suggest that the organization and electrophysiological properties of synaptic kainate receptors are modified by association with members of the SAP90/PSD-95 family.

An evidenced-based clinical pathway for acute appendicitis decreases hospital duration and cost

BACKGROUND/PURPOSE

In the pediatric population, appendicitis remains the most common surgical emergency encountered. The purpose of this study was to determine the impact of an evidence-based clinical pathway for acute appendicitis on patient care as well as hospital and home care costs at the authors' pediatric institution.

METHODS

A prospective evaluation was conducted of an appendicitis clinical pathway (June 1996 through November 1996) compared with historical control patients (June 1994 through November 1994) not cared for by the pathway.

RESULTS

Data (average +/- SD) for 120 pathway (P) patients were compared with 122 control (C) patients. Age (11.5 +/- 3.6 years for C v 11.2 +/- 3.9 years for P), rates of negative appendectomy (12.3% for C v 9.2% for P) and perforation (26.2% for C v 18.3% for P) were similar. Pathway patients with nonperforated appendicitis were more often discharged from the hospital within 24 hours (48% for C v 67% for P; P = .014) with lower hospital costs ($4,095 +/- $1,280 for C v $3,638 +/- $1,633 for P; P = .001). Pathway patients with perforated appendicitis had shorter hospitalization (185.2 +/- 59 hours for C v 113 +/- 44 hours for P; P = .0001) and lower hospital costs ($11,175 +/- $3,893 for C v $7,823 +/- $2,366 for P; P = .0001).

CONCLUSION

An evidence-based appendicitis pathway decreased duration of hospitalization and cost without adversely affecting diagnosis or therapy. Clinical pathways for surgical diagnoses may prove useful as a means to minimize costs without compromising patient care.

Biomechanical evaluation of posterior and anterior lumbar interbody fusion techniques

This study determined the biomechanical differences between anterior and posterior lumbar interbody fusion (ALIF and PLIF). Ten cadaveric spines were tested. Five specimens had ALIF and five had PLIF at L4-L5. Stabilization was performed with pedicle screws and rods (Cotrel-Dubboset, Sofamor-Danek, Memphis, TN, U.S.A.). Angular motion was measured in flexion, extension, bending, and torsion on the intact, instrumented, and "fused" specimens. Instrumentation alone caused a significant decrease in segmental motion in all loading modes (p < 0.01). After the simulated fusion procedures, all specimens were most stable in flexion, and significantly less stable in extension (p = 0.04). Comparing directly, ALIF was significant more stable in left torsion (p = 0.03) with trends in left bending (p = 0.08) and right torsion (p = 0.07). Thus, from a purely biomechanical perspective, ALIF appears to be slightly superior to PLIF.

Oxidative-hepatic injury of isoniazid-rifampicin in young rats subjected to protein and energy malnutrition

The role of protein and energy malnutrition in the pathogenesis of isoniazid (INH)-rifampicin (RMP) induced hepatic injury was investigated. Status of oxidative/antioxidative profile was the mechanistic approach to enumerate the nature of injury. Weanling rats were fed with ad-libitum quantity of isocaloric diets containing 5% casein based proteins for the production protein and energy malnutrition. INH and RMP (50 mg/kg of each) were injected intraperitonially for a period of two weeks. Analysis of serum transaminases and histopathological observations revealed hepatic injury. Hepatic thiols and blood glutathione were decreased significantly in INH and RMP treated groups. Among antioxidative enzymes, hepatic superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferases (against CDNB and DCNB substrates) showed significant decline of activities in INH and RMP treated groups. The activities of hepatic glutathione reductase, glutathione-S-transferase (against EA substrate) and lipid peroxidation observed significant elevation. A careful comparison of protein and energy restriction revealed a greater degree of oxidative-stress of INH-RMP in protein-restriction.