Neurodevelopmental outcome of 'at risk' nursery graduates

A cohort study at a tertiary care neonatal service was undertaken to determine the neurodevelopmental outcome of neonates who required intensive care. One hundred and nineteen nursery graduates were enrolled for follow up if they fulfilled any of the following risk factors: birth weight less than 1500 g, Apgar score less than 4 at 5 minutes, seizure(s), and required assisted ventilation for more than 24 hours. They were subjected to periodic clinical evaluation and administered the Bayley Scales of Infant Development in early childhood. Of the total infants enrolled, 101 completed the required follow up. They included 55 infants with birth weight < 1500 g, 45 with low Apgar scores, 12 with seizure(s) and 28 who received assisted ventilation. An overwhelming majority of subjects (85%) had normal neurodevelopmental outcome. The adverse outcome in the remaining 15 included mental retardation in all, subnormal motor development in 14, microcephaly in 1, hearing loss in 2 and visual impairment in 4. Among the neonatal risk factors, seizures, sepsis and hypoxic ischemic encephalopathy had a significant association with adverse outcome. Despite serious neonatal morbidity, the early neurodevelopmental outcome of nursery graduates was reasonably good. The association of neonatal sepsis with neurodevelopmental sequelae merits a prospective evaluation.

Association of genital mycoplasma colonization with low birth weight

OBJECTIVE

This study was conducted to document the prevalence of maternal genital tract colonization by Ureaplasma urealyticum and Mycoplasma hominis, and to assess its association with low birth weight (LBW) and prematurity.

METHODS

The high vaginal swabs of pregnant women in spontaneous labor after 26 weeks of gestation were cultured for U. urealyticum and M. hominis. Clinical details and perinatal outcomes including birth weight and gestation were documented.

RESULTS

Of a total of 303 women enrolled, 148 (48.8%) had positive vaginal cultures for U. urealyticum, while only five (1.6%) grew M. hominis. The mean birth weight and the incidences of LBW and preterm neonates among ureaplasma positive and ureaplasma negative mothers were statistically comparable.

CONCLUSIONS

U. urealyticum emerged as a common inhabitant of the lower genital tract of women in labor, being present in nearly half of them. Its presence was not a risk factor of LBW or prematurity. Maternal colonization with M. hominis was uncommon.

Human T- and B-cell reactivity to the 16kDa alpha-crystallin protein of Mycobacterium tuberculosis

The attributes of immunodominance, predominant expression during mycobacterial dormancy and restriction to the Mycobacterium tuberculosis complex make the 16 kDa protein an important candidate for the study of the immune response in humans. We therefore investigated the relationship between T- and B-cell reactivity to the recombinant antigen and disease in a total of 127 subjects. The percentage of T-cell responders towards both the intact antigen and its permissively recognised peptide 16p91-110 was highest in healthy bacillus Calmette-Guérin (BCG)-sensitized controls (96% and 68%, respectively) and lowest in those with extensive untreated tuberculosis (26% and 18%) (P < 0.001). By contrast, antibody levels (ABT50 > 100) were highest in patients with extensive disease (46-50%) (P < 0.005). There was significantly higher production of IFN-gamma in the BCG-sensitized controls by comparison with untreated patients (P < 0.05), but complete antituberculous chemotherapy abolished this deficit in patients. The significance of these findings to immunodiagnosis and protective immunity is discussed.

Diffuse leptomeningeal gliomatosis associated with multifocal CNS infarcts

BACKGROUND

Widespread dissemination of astrocytoma throughout the cerebrospinal fluid is unusual, especially as the initial presentation in a patient, and association with cerebral infarcts is rare. CASE DESCRIPTION A 47-year-old man subacutely developed progressive headache and backache, vomiting, altered consciousness, and numbness in both arms. Brain computerized axial tomography showed calcification in the fourth ventricle and magnetic resonance imaging demonstrated diffuse meningeal enhancement, a lesion in the canal of Magendie, and T2-weighted hyperintense lesions in several locations. Angiography showed vasospasm/vasculopathy involving multiple cerebral vessels. Biopsy of the fourth ventricular mass revealed a subependymoma with an overlying leptomeningeal anaplastic astrocytoma with numerous Rosenthal fibers. The patient was treated with three doses of intrathecal methotrexate via lumbar puncture but suddenly became unresponsive and died 6 days later, 8 weeks after initial symptoms. Autopsy demonstrated the subependymoma and a widespread leptomeningeal anaplastic astrocytoma, which showed no clear-cut origin from the subependymoma, but microscopically infiltrated the left medial temporal lobe. Multiple subacute and acute infarcts of the brain, brain stem, and upper spinal cord were seen only in areas with leptomeningeal tumor. CONCLUSION Glioma cells surrounding and focally permeating central nervous system vessels without lumenal occlusion can lead to vasospasm and widespread infarcts.

The role of the p53 protein in the selective vulnerability of the inner retina to transient ischemia

PURPOSE

To determine whether the p53 protein plays a role in the selective vulnerability of the inner retina to transient ischemia.

METHODS

Transient retinal ischemia was induced using a high intraocular pressure (HIOP) model in the Sprague-Dawley rat for 60 minutes. Histopathologic outcome was determined 7 days after ischemia. In addition, analysis for evidence for apoptosis (TdT-dUTP terminal nick-end label [TUNEL] staining) and p53 protein expression (immunohistochemistry) was performed at several points during the reperfusion period. In a separate set of experiments, wild-type mice and two groups of transgenic mice, one homozygous and the other heterozygous for the p53 null gene, were also subjected to HIOP for 60 minutes, and histopathology was performed 7 days later.

RESULTS

At 7 days subsequent to 60 minutes of ischemia in the rat, there was marked thinning of the inner retinal layers. There were scattered TUNEL-positive cells within the inner retina, peaking at 24 to 48 hours and persisting for at least 7 days. p53 immunochemistry demonstrated elevated protein levels within the inner retina; this finding peaked at 24 to 48 hours but was no longer present at 4 days after ischemia. TUNEL staining of the inner retina of the mouse was most prominent 24 hours subsequent to ischemia but persisted at 48 hours. Seven days subsequent to 60 minutes of ischemia in the wild-type and transgenic mice, histopathologic evaluation demonstrated preservation of the retinal histoarchitecture in the heterozygous group compared with the wild-type or homozygous animals.

CONCLUSIONS

These data further support the hypothesis that the delayed cell death that occurs after transient retinal ischemia is, in part, apoptotic. In addition, they suggest a role for the p53 protein in the selective vulnerability of the inner retina to transient ischemia. p53 protein may be a target for future therapeutic agents in the treatment of disorders of the retina where ischemia plays a pathogenetic role.

Use of citric acid for neutralizing polymerase chain reaction inhibition by chlorogenic acid in potato extracts

Polyphenolics are a widely distributed class of plant constituents implicated in the inhibition of the polymerase chain reaction (PCR). Since chlorogenic acid forms the bulk of phenolics in the potato tuber, a range of chlorogenic acid concentrations were tested for inhibition of reverse transcription (RT) and PCR steps. The RT step was inhibited at chlorogenic acid concentrations of 6.0 to 7.5 microg, while the PCR step was inhibited at much lower concentrations of 1.2 to 1.8 microg. Incorporation of 1.2% citric acid at the nucleic acid extraction step prevented darkening of the extract and neutralized the inhibitory effect of chlorogenic acid.

Effect of prenatal diazepam, phenobarbital, haloperidol and fluoxetine exposure on foot shock induced aggression in rats

Different groups of pregnant rats were treated with diazepam (10 mg/kg), phenobarbital (10 mg/kg), haloperidol (0.1 mg/kg), fluoxetine (10 mg/kg) and vehicle (normal saline) intraperitoneally once a day during gestation days 13 to 21. After birth these pups were culled to 8 pups/dam and foster-nursed by lactating mothers for 3 weeks and were reared in colony cages thereafter. Sex and weight matched pairs of rat offsprings were subjected to foot shock induced aggression test at 8 weeks of age. Two parameters of aggressive behaviour were recorded namely, the latency to fight and total number of fighting bouts. The results indicate that prenatal exposure to diazepam, phenobarbital, haloperidol and fluoxetine caused significantly enhanced aggression in terms of number of fighting bouts.

Autonomic functions in restrictive cardiomyopathy and constrictive pericarditis: a comparison

BACKGROUND

This study was undertaken to analyze autonomic functions in restrictive cardiomyopathies. Restrictive cardiomyopathies have clinical and hemodynamic similarity with chronic constrictive pericarditis. Autonomic dysfunction has been described in the latter.

METHODS AND RESULTS

Autonomic function analysis has not been reported in restrictive cardiomyopathy. Six consecutive patients with restrictive cardiomyopathy were included in this study (5 men, 1 woman, mean age 35+/-5.4 years). The tests performed were designed to test the sympathetic efferent pathway, that is, by cold hand immersion and loud noise tests, parasympathetic efferent pathway by Valsalva ratio and expiration/inspiration ratio and the baroreceptor function by testing their sensitivity slope. The results were compared with 20 patients with chronic constrictive pericarditis and with 10 healthy age- and sex-matched control subjects previously studied. The rise of systolic blood pressure after cold hand immersion and sudden loud noise was not significantly different compared with control subjects. The expiration/inspiration ratio was 1.1+/-0.01 compared with 1.57+/-0.1 in the control group (p < 0.01). The Valsalva ratio was significantly lower (1.1+/-0.04) compared with control subjects (1.83+/-0.1, p < 0.01). The baroreceptor sensitivity was not reduced compared with that in control subjects. In comparison to constrictive pericarditis, sympathetic efferent pathway is preserved in restrictive cardiomyopathy (p < 0.0001). The parasympathetic efferent pathway is borderline abnormal in restrictive cardiomyopathy but not significantly as compared with constrictive pericarditis (p=not significant). The baroreceptor sensitivity slope is normal in patients with restrictive cardiomyopathy as compared with significant depression seen in constrictive pericarditis (p < 0.05). Autonomic functions are better preserved in patients with restrictive cardiomyopathies compared with chronic constrictive pericarditis.

CONCLUSIONS

Autonomic dysfunction is localized to parasympathetic efferent pathway. This is in comparison to constrictive pericarditis, in which severe autonomic dysfunction is a universal feature and includes all segments of autonomic nervous system.

Two-year follow-up of a prospective randomised trial of electrovaporization versus resection of prostate

OBJECTIVES

Transurethral electrovaporization of the prostate (TUVP) has become a popular, minimally invasive procedure to treat BPH with promising initial results. This study was conducted to compare the efficacy, safety and durability of TUVP with standard TURP. We report the 2-year follow-up.

METHODS

104 consecutive men with BPH admitted for surgery were randomised to TUVP (52 patients, mean age: 67.5 years) or TURP (52 patients, mean age: 70.2 years). 47 patients in each arm completed 2-year follow-up.

RESULTS

Follow-up data at 2 years show a comparable, significant and maintained improvement in mean IPSS (TUVP: 4.3 vs. TURP: 6.3), quality of life score (TUVP: 1. 1 vs. TURP: 1.7), and maximum flow rate (TUVP: 22.4 vs. TURP: 21.2 ml/s) with fall in mean post-void residual volume (TUVP: 18.8 vs. TURP: 22.8 ml). Postoperative impotence reported in TUVP: 17% vs. TURP: 11% (p = 0.49) and retrograde ejaculation TUVP: 72% vs. TURP: 89% (p = 0.47). Two patients in each arm (4%) had urethral stricture and 2 patients (4%) in the resected group had bladder neck stricture. Four patients in each group required re-operation for residual adenoma during the 2 years (4% in each arm each year).

CONCLUSIONS

Our 2 years' follow-up results suggest that TUVP is as effective as standard TURP in the treatment of moderate-sized BPH with comparable durability.

Sequence, heterologous expression and functional characterization of a novel tryparedoxin from Crithidia fasciculata

Tryparedoxin has recently been discovered as a constituent of the trypanosomal peroxidase system catalysing the reduction of a peroxiredoxin-type peroxidase by trypanothione [Nogoceke et al. (1997) Biol. Chem. 378, 827-836] and has attracted interest as a potential molecular target for the development of trypanocidal agents. Here we describe the first isolation of a novel gene from Crithidia fasciculata encoding a different tryparedoxin designated tryparedoxin II. The deduced amino acid sequence of tryparedoxin II (accession number AF055986) differs substantially from the partial sequence reported for the tryparedoxin described previously and now renamed tryparedoxin I. It shares the sequence motif Vx3FSAxWCPPCR shown to represent the catalytic site in tryparedoxin I [Gommel et al. (1997) Eur. J. Biochem. 248, 913-918] with mouse nucleoredoxin (accession number X92750), and a thioredoxin-like gene product of Caenorhabditis elegans (accession number U23511). Depending on which ATG is considered functional as translation start codon, tryparedoxin II, with 150 or 165 amino acid residues, is 50% larger than the typical thioredoxins. The tryparedoxins appear phylogenetically related to the thioredoxins, but sequence similarities are restricted to the active site motifs and their intimate neighbourhood. His-tagged tryparedoxin II expressed in E. coli exhibited ping-pong kinetics in the trypanothione:peroxiredoxin assay with kinetic parameters (KM peroxiredoxin = 4.2 microM, KM trypanothione = 33 microM, Vmax/[E] = 952 min(-1)) similar to those reported for tryparedoxin I [Gommel et al. (1997) Eur. J. Biochem. 248, 913-918]. The co-existence of two distinct tryparedoxins in C. fasciculata suggests diversified biological roles of this novel type of protein, which in trypanosomatids may substitute for the pleiotropic redox catalyst thioredoxin.

Mechanism of inhibition of benzo[a]pyrene-induced forestomach cancer in mice by dietary curcumin

Curcumin (diferuloylmethane), the major yellow pigment in turmeric, has been shown to inhibit benzo[a]pyrene (BaP)-induced forestomach cancer in mice through mechanism(s) not fully understood. It is well known that while cytochrome P4501A1 (CYP1A1) and epoxide hydrolase (EH) are important in the conversion of BaP to its activated form, (+)-anti-7,8-dihydroxy-9,10-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene [(+)-anti-BaPDE], the detoxification of (+)-anti-BaPDE is accomplished by glutathione (GSH) S-transferases (GST). Therefore, it seems reasonable to postulate that curcumin may exert anti-carcinogenic activity either by inhibiting activation of BaP or (and) by enhancing the detoxification of (+)-anti-BaPDE. Administration p.o. of 2% curcumin in the diet to female A/J mice for 14 days, which has been shown to cause a significant inhibition in BaP-induced forestomach tumorigenesis, resulted in a modest but statistically significant reduction in hepatic ethoxyresorufin O-deethylase (EROD) activity, a reaction preferentially catalyzed by CYP1A1. While EROD activity could not be detected in the forestomach of either control or treated mice, curcumin feeding caused a statistically significant increase (approximately 2.3-fold) in hepatic EH and GST activities. Hepatic and forestomach GSH levels, and forestomach EH and GST activities were not affected by curcumin treatment. Even though the levels of various hepatic GST isoenzymes were significantly increased upon curcumin feeding, maximum induction was noticed for the pi class isoenzyme (mGSTP1-1), which among murine hepatic GSTs is highly efficient in the detoxification of (+)-anti-BaPDE. In conclusion, the results of the present study suggest that curcumin may inhibit BaP-induced forestomach cancer in mice by affecting both activation as well as inactivation pathways of BaP metabolism in the liver.

Discordance between FDG uptake and technetium-99m-HMPAO brain perfusion in acute traumatic brain injury

A 28-yr-old woman who sustained a mild traumatic brain injury had an 18F-fluorodeoxyglucose (FDG) PET brain study using coincidence imaging performed on a dual-head gamma camera (MCD version; ADAC, Milpitas, CA) followed 24 hr later by 99mTc-hexamethyl propyleneamine oxime SPECT brain perfusion imaging using a triple-head gamma camera (TRIONIX, Twinsburg, OH). The results of the SPECT brain perfusion study demonstrated decreased frontoparietal cortical brain perfusion, whereas 18F-FDG cerebral uptake was normal. Neuropsychological evaluation suggested frontal lobe involvement. This case demonstrates the possibility of discordance between brain perfusion and glucose uptake in acute mild traumatic brain injury.

Identification of new cytotoxic T-cell epitopes on the 38-kilodalton lipoglycoprotein of Mycobacterium tuberculosis by using lipopeptides

Induction of cytotoxic T lymphocytes (CTLs) by vaccination has been shown to protect against bacterial, viral, and tumoral challenge. The aim of this study was to identify CTL epitopes on the 38-kDa lipoglycoprotein from Mycobacterium tuberculosis. The identification of these CTL epitopes was based on synthesizing peptides designed from the 38-kDa lipoglycoprotein, with known major histocompatibility complex class I (MHC-I) binding motifs (H-2Db), and studying their ability to up-regulate and stabilize MHC-I molecules on the mouse lymphoma cell line RMA-S. To improve the capacity of the identified peptides to induce CTL responses in mice, palmitic acid with a cysteine-serine-serine spacer amino acid sequence was attached to the amino terminus of the peptide. Two of five peptides with H-2Db binding motifs and their corresponding lipopeptides up-regulated and stabilized the H-2Db molecules on RMA-S cells. Both lipopeptides, in combination with incomplete Freund's adjuvant, induced CTL responses in C57BL/6 (H-2(b)) mice. Moreover, the lipopeptide induced stronger CTL responses than the peptide. The capacity of the various lipopeptides to induce CTL displayed a good relationship with the ability of the (lipo)peptide to up-regulate and to stabilize H-2Db molecules. The capacity of the peptides and lipopeptides to up-regulate and stabilize MHC-I expression can therefore be used to predict their potential to function as a CTL epitope. The newly identified CTL epitopes and their lipid derivatives provide us with important information for future M. tuberculosis vaccine design.

Sequential analysis of the influence of blood storage on aggregation, deformability and shape parameters of erythrocytes

The hemorheological and morphological changes in blood during storage under standardised conditions for 35 days were analysed by sequential determination of the variability of aggregation, deformability and shape of erythrocytes. The shape analysis was carried out by shape descriptors based on the projected area and perimeter, as measured by processing of erythrocyte images obtained from blood smears. The aggregation of erythrocytes was analysed from the data on the sequential variation of transmitted laser intensity after passing through the erythrocyte suspension. Similarly, the deformability of erythrocytes was determined in terms of passage time as obtained by analysis of flow of erythrocyte suspension through the cellulose membrane. The results show that the erythrocyte aggregation parameters and shape descriptors show significant variation, whereas the deformability is reduced (up to 5%) compared with that of the fresh samples. These variations may explain the observed changes in blood viscosity and viability of erythrocytes after their infusion in to the cardiovascular system.

Study of azathioprine encapsulation into liposomes

The factors influencing the encapsulation of azathioprine (AZA) into liposomes were investigated to find out the conditions for its optimal entrapment. Similar studies for comparison were also carried out on 6-mercaptopurine (6-MP), of which AZA is a prodrug. AZA and also 6-MP show higher encapsulation efficiencies in MLVs as compared to LUVs. Variation in phospholipid composition does not seem to affect the loading capacity of either of the two drugs. The encapsulation efficiency of both the drugs improves upon addition of cholesterol in the bilayer, but the effect is seen only up to 30% cholesterol. Thereafter the effect becomes constant. AZA shows better incorporation in the positively charged liposomes as compared to those with neutral or negative charge. The entrapment of 6-MP is, however, found to be independent of the charge on the liposomes. Entrapment efficiency for both the drugs markedly depends on the pH of the hydration medium, yielding better entrapment efficiencies at high pH values. The rise in solute concentration initially causes increase in the entrapment of the two drugs which is followed by a decreasing phase.

Novel delivery systems for coagulation proteins

Long-term haemophilia prophylaxis with clotting factors administered by alternative delivery modes requires stable liquid formulations of these factors. We developed an aqueous-formulated human coagulation factor IX (hCFIX) with in vitro half-life (T 1/2) of 6 weeks at 37 degrees C and 18 months at 4 degrees C. Upon bolus subcutaneous (s.c.) injection in animals, hCFIX had a bioavailability of up to 16% compared to intravenous (i.v.) dose. When delivered by s.c. implanted pumps, hCFIX attained > 2% of normal human levels in the animal plasma. Hydrogels of hCFIX in a chitosan derivative, N,O-carboxymethyl chitosan (NOCC), released hCFIX slowly in vitro, and when injected s.c., gave prolonged plasma levels over those obtained by bolus i.v. or s.c. injection. Freeze-dried human coagulation factor VIII (hCFVIII) formulated in non-aqueous solvents had in vitro T 1/2 up to 80 days at 37 degrees C.

Possible mechanism of captopril induced endothelium-dependent relaxation in isolated rabbit aorta

The mechanism of captopril, an angiotensin converting enzyme (ACE) inhibitor with sulfhydryl group (SH) in its structure, to produce an endothelium-dependent vasorelaxation was studied. In rabbit aorta with intact endothelium and precontracted with phenylephrine, captopril and superoxide dismutase (SOD) produced dose-dependent relaxation. Lisinopril, an ACE inhibitor without a -SH group in its structure, did not produce endothelium-dependent relaxation. It was observed that captopril, like SOD, produced the relaxation by protecting the EDRF from getting inactivated by superoxide anions as pyrogallol and methylene blue inhibited both the captopril and SOD-mediated relaxation. The free radical scavenging action of captopril is further substantiated by the observation that captopril, but not lisinopril, inhibited FeCl3/ascorbic acid-induced lipid peroxidation in whole tissue homogenates of rabbit aorta to a level comparable to that of SOD. These results suggest that endothelium-dependent vasodilation produced by captopril may be due to its ability to scavenge superoxide anion and this property may be ascribed to the -SH group present in its structure.