Real time blood flow velocity monitoring in the microcirculation

A real-time monitoring system based on the dual slit methodology for the characterization of the red blood cell velocity at the level of microcirculation has been developed. The analog photometric signals are acquired and processed using a hybrid hardware-software system that exploits a A/D conversion and an optimized correlation algorithm on an embedded system. It is implemented exploiting the resources of a general purpose board capable to extract the useful information from the noisy photometric signals, to process them, to show and save the results and, therefore, to make the experiments reproducible. Two different approaches to the crosscorrelation algorithm have been tested and their performances have been compared to each. The system has been tested in in vivo experiments on anaesthetized hamsters. Several microvessels have been observed and the results have been compared to the output of an analog crosscorrelator to verify their coherence.

Fluconazole prophylaxis in extremely low birth weight infants: association with cholestasis

BACKGROUND

Extremely low birth weight (ELBW) infants are at increased risk for invasive candidiasis and associated morbidity and mortality. The use of fluconazole prophylaxis in this population has raised a benefit versus risk concern among clinicians.

OBJECTIVES

To evaluate the effectiveness and safety of fluconazole prophylaxis in ELBW infants.

STUDY DESIGN

ELBW infants (BW<or=1,000 g) born during the pre-prophylaxis era (PPE, January 1998-February 2002) were compared with prophylaxis era (PE, March 2002-September 2005). Infants born during PE received fluconazole prophylaxis for 6 weeks, as long as they had intravenous access. Demographic and clinical data were collected. The two groups were compared for baseline demographics, risk factors for candidiasis, the incidence of invasive candidiasis, liver enzymes, alkaline phosphatase, and bilirubin (total and direct).

RESULTS

Nine out of 137 infants (6.6%) developed invasive candidiasis during PPE compared to none of 140 (0%) during PE (P=0.006). During PE, 60/140 (42.9%) infants developed conjugated hyperbilirubinemia compared to 12/137 (8.8%) during PPE (P<0.001).

CONCLUSION

Although a fluconazole prophylaxis regimen for ELBW infants was effective in preventing invasive candidiasis, an increase in the incidence of conjugated hyperbilirubinemia was observed. Further studies are needed to evaluate the safety of fluconazole prophylaxis in this population.

MRI and 1H-MRS findings in early-onset cobalamin C/D defect

OBJECT

Cobalamin C/D defect is an inborn error of cobalamin metabolism causing methylmalonic aciduria and homocystinuria. The early-onset form is characterized by severe neurological impairment. The aim of this study was to evaluate and monitor brain damage in early-onset cbl-C/D defect by conventional MRI and to assess the additional value of 1H-MRS.

METHODS

We retrospectively examined serial MRI studies of 7 patients, performed on a 1.5 T system. Four patients had the first evaluation within the first 4 months of life and three later. The imaging protocol included spin-echo T1-weighted, T2-weighted, IR, and FLAIR. Five patients underwent 1H-MRS, using chemical shift imaging (CSI) in three patients and single voxel spectroscopy (SVS) in two.

RESULTS

Three of the patients studied early showed tetraventricular hydrocephalus and diffuse swelling of supratentorial white matter with involvement of the "U" fibres. Two showed patchy cavitating lesions in the basal ganglia. White matter changes became evident at a later stage. In three cases 1H-MRS showed an abnormal peak of lactate in the basal ganglia or in the periventricular white matter.

CONCLUSIONS

Our study shows severe heterogeneous brain MR abnormalities in cbl-C/D defect. We observed unusual basal ganglia lesions in 30 % of our cases and also found a high incidence of hydrocephalus and supratentorial white matter abnormalities.

A multi-functional, portable device with wireless transmission for home monitoring of children with a learning disability

A portable monitoring device was developed to assist in the management of children with a learning disability. The device was designed for continuous home monitoring of blood oxygen saturation, heart and respiration rates, and patient activity. It could be worn on a belt, while the patient continued normal activities. Data were stored on a multimedia card and automatically transmitted to a PC at prescribed intervals via a Bluetooth wireless link. From the PC the data were transmitted to a Web server, where the information was made available to the staff involved in the patient's care. Preliminary clinical studies were performed with nine patients (four with Down's syndrome, three with cerebral palsy and two with mental retardation). Patients and families considered the device easy to use and to wear. The monitoring device identified events of possible clinical interest. Although it was designed for monitoring children with a learning disability, it may also be useful with other groups, such as elderly people.

Assessment of the fetal nasal bone at 11-14 weeks of gestation by three-dimensional ultrasound

OBJECTIVE

To evaluate the benefit of three-dimensional (3D) ultrasound in the examination of the fetal nasal bone at 11-14 weeks of gestation.

METHOD

We examined the fetal nasal bone in 120 stored volumes acquired transabdominally with a 3D scanner from singleton pregnancies at 11-14 weeks of gestation. The volume acquisition had been performed following conventional ultrasound examination that had demonstrated presence of the fetal nasal bone. The volumes were obtained with two-dimensional (2D) start images in transverse, coronal mid-sagittal, parasagittal and oblique longitudinal sections of the fetal head.

RESULTS

In the transverse and coronal sections, a satisfactory image demonstrating presence of the nasal bone was achieved in only three and one, respectively, of the 20 volumes that we obtained. In mid-sagittal sections, the nasal bone was always visible when the angle was within a range of 30-60 degrees, without the need for sectional image analysis. None of the images with an angle >60 degrees or <30 degrees was satisfactory. In the parasagittal sections with the fetal profile at 45 degrees, a good-quality image of the nasal bone was possible in all cases that were examined, irrespective of the distance from the mid-sagittal plane. In the oblique longitudinal sections with the fetal profile at 45 degrees, there were 10 volumes where the 2D start section was at 0-25 degrees from the midline and in all these cases the nasal bone was successfully visualized. In contrast, only 5/20 cases where the 2D start section was at 25-90 degrees from the midline provided a satisfactory image demonstrating the nasal bone. In 5/10 volumes obtained with the fetus facing downwards the nasal bone was visible in both the 2D and 3D images.

CONCLUSION

In a 3D volume the extent to which the nasal bone can be demonstrated to be present in a given reconstructed section is entirely dependent on obtaining a good initial 2D view.

Femur and humerus length in trisomy 21 fetuses at 11-14 weeks of gestation

OBJECTIVE

To determine the value of measuring fetal femur and humerus length at 11-14 weeks of gestation in screening for chromosomal defects.

METHODS

Femur and humerus lengths were measured using transabdominal ultrasound in 1018 fetuses immediately before chorionic villus sampling for karyotyping at 11-14 weeks of gestation. In the group of chromosomally normal fetuses, regression analysis was used to determine the association between long bone length and crown-rump length (CRL). Femur and humerus lengths in fetuses with trisomy 21 were compared with those of normal fetuses.

RESULTS

The median gestation was 12 (range, 11-14) weeks. The karyotype was normal in 920 fetuses and abnormal in 98, including 65 cases of trisomy 21. In the chromosomally normal group the fetal femur and humerus lengths increased significantly with CRL (femur length = - 6.330 + 0.215 x CRL in mm, r = 0.874, P < 0.0001; humerus length = - 6.240 + 0.220 x CRL in mm, r = 0.871, P < 0.0001). In the Bland-Altman plot the mean difference between paired measurements of femur length was 0.21 mm (95% limits of agreement - 0.52 to 0.48 mm) and of humerus length was 0.23 mm (95% limits of agreement - 0.57 to 0.55 mm). In the trisomy 21 fetuses the median femur and humerus lengths were significantly below the appropriate normal mean for CRL by 0.4 and 0.3 mm, respectively (P = 0.002), but they were below the respective 5th centile of the normal range in only six (9.2%) and three (4.6%) of the cases, respectively.

CONCLUSION

At 11-14 weeks of gestation the femur and humerus lengths in trisomy 21 fetuses are significantly reduced but the degree of deviation from normal is too small for these measurements to be useful in screening for trisomy 21.

Single umbilical artery at 11-14 weeks' gestation: relation to chromosomal defects

OBJECTIVE

To determine the possible association between single umbilical artery (SUA) at 11-14 weeks of gestation and the incidence of chromosomal abnormalities.

METHODS

Color flow imaging of the fetal pelvis was used to determine the number of umbilical arteries in 717 fetuses immediately before chorionic villus sampling for karyotyping at 11-14 weeks' gestation.

RESULTS

Single umbilical artery (SUA) was diagnosed in 21/634 (3.3%) chromosomally normal fetuses, in 5/44 (11.4%) with trisomy 21, 14/18 (77.8%) with trisomy 18 and 2/21 (9.5%) with other chromosomal defects. In the chromosomally normal group there was no significant difference in median fetal crown-rump length or nuchal translucency (NT) between those with a single and those with two umbilical arteries. In the 42 fetuses with SUA the expected number of cases of trisomy 21, estimated on the basis of maternal age, gestational age and fetal NT, was 4.7, which was not significantly different from the observed 5. The corresponding numbers for trisomy 18 were 2.0 for expected and 14 for observed (Fisher's exact test P = 0.0016).

CONCLUSION

A SUA at 11-14 weeks' gestation has a high association with trisomy 18 and other chromosomal defects.

Absent nasal bone at 11-14 weeks of gestation and chromosomal defects

OBJECTIVE

To examine the association between absence of the nasal bone at the 11-14-week ultrasound scan and chromosomal defects.

METHODS

Ultrasound examination was carried out in 3829 fetuses at 11-14 weeks' gestation immediately before fetal karyotyping. At the scan the fetal crown-rump length (CRL) and nuchal translucency (NT) thickness were measured and the fetal profile was examined for the presence or absence of the nasal bone. Maternal characteristics including ethnic origin were also recorded.

RESULTS

The fetal profile was successfully examined in 3788 (98.9%) cases. In 3358/3788 cases the fetal karyotype was normal and in 430 it was abnormal. In the chromosomally normal group the incidence of absent nasal bone was related firstly to the ethnic origin of the mother (2.8% for Caucasians, 10.4% for Afro-Caribbeans and 6.8% for Asians), secondly to fetal CRL (4.6% for CRL of 45-54 mm, 3.9% for CRL of 55-64 mm, 1.5% for CRL of 65-74 mm and 1.0% for CRL of 75-84 mm) and thirdly, to NT thickness, (1.8% for NT < 2.5 mm, 3.4% for NT 2.5-3.4 mm, 5.0% for NT 3.5-4.4 mm and 11.8% for NT > or = 4.5 mm. In the chromosomally abnormal group the nasal bone was absent in 161/242 (66.9%) with trisomy 21, in 48/84 (57.1%) with trisomy 18, in 7/22 (31.8%) with trisomy 13, in 3/34 (8.8%) with Turner syndrome and in 4/48 (8.3%) with other defects.

CONCLUSION

At the 11-14-week scan the incidence of absent nasal bone is related to the presence or absence of chromosomal defects, CRL, NT thickness and ethnic origin.

Positive effect on T-cell regulatory apoptosis by mycophenolate mofetil

The regulatory benefit of apoptosis (activation-induced cell death, AICD) in T cells may be impacted by immunosuppressive agents. We examined this for mycophenolate mofetil (MMF) compared with cyclosporine (CYA). Peripheral blood leukocytes (PBL) were stimulated by either Staph enterotoxin B (SEB) or by anti-CD3 plus anti-CD28. Cell division analysis (sequential reduction in carboxyflourescein diacetate succinimidyl ester, CFSE) was used to measure proliferation and determine status of different cell generations. Apoptosis was measured by annexin V staining, and FasL expression by anti-FasL antibody staining, of activated cells using flow cytometry. CSA and mycophenolic acid (MPA, the active agent of MMF) were added in titration in 3-day cultures. We found that CSA caused diminution in apoptosis but MPA increased it with SEB stimulation. The CSA effect on apoptosis was present when a more calcineurin-dependent stimulus. anti-CD3+ anti-CD28, was used but the MPA effect was less, producing a decrease only in the undivided cells. To look more directly at the differential effect on calcineurin-dependent AICD gene induction of the two agents, we measured Fas-L expression with anti-CD-3 + CD28 stimulation, and confirmed that CYA caused a major decrement in appearance of Fas-L, whereas MPA caused a converse accumulation of it. This seems to be explained by the block more distal in cell activation, resulting in a build-up of a precursor in the activation pathways. We conclude that MMF treatment may be rationale as an adjunct to calcineurin inhibitor treatment because of its converse effect on T cell regulatory apoptosis.

Neurofibromatosis type 1 presenting with hand dystonia

Neurofibromatosis type 1 is frequently associated with increased intensity T2-weighted magnetic resonance imaging (MRI) brain abnormalities, called "unidentified bright objects." Unidentified bright objects are generally held to be benign and tend to decrease in size during adulthood. We describe a case of neurofibromatosis type 1 with a similar thalamic and subthalamic MRI abnormality associated with contralateral hand dystonia. Over a 2-year follow-up, the lesions showed a reduction in size apparently correlated with a reduction in symptoms.

Ataxia, deafness, leukodystrophy: inherited disorder of the white matter in three related patients

The authors report three related patients, two girls and a boy, presenting a distinctive clinical phenotype characterized by early-onset, slowly progressive ataxia. Subsequently these patients experienced sensorineural deafness, resulting in complete hearing loss by the age of 12 years, and exhibited leukodystrophy on brain MRI. There was no mental deterioration. An extensive neurometabolic assessment failed to detect any anomalies in the three patients. The patients originated from a large consanguineous family in southern Italy (Calabria), with a pedigree that was traced back five generations. The disease's pattern of transmission suggests an autosomal recessive trait.

The polo-like kinase PLK-1 is required for nuclear envelope breakdown and the completion of meiosis in Caenorhabditis elegans

The Polo-like kinases are key regulatory molecules required during the cell cycle for the successful completion of mitosis. We have cloned a C. elegans homolog of the Drosophila melanogaster polo gene (designated plk-1 for C. elegans polo-like kinase-1) and present the subcellular localization of the PLK-1 protein during the meiotic and mitotic cell cycles in C. elegans oocytes and embryos, respectively. Disruption of PLK-1 expression by RNA-mediated interference (RNAi) disrupts normal oocyte and embryonic development. Inspection of oocytes revealed a defect in nuclear envelope breakdown (NEBD) before ovulation. This defect in NEBD was also observed in oocytes that were depleted of the cyclin-dependent kinase NCC-1 (C. elegans homolog of Cdc2). The plk-1 RNAi oocytes were fertilized; however the resulting embryos were unable to separate their meiotic chromosomes or form and extrude polar bodies. These defects led to embryonic arrest as single cells. genesis 26:26-41, 2000. Published 2000 Wiley-Liss, Inc.

Regulation of JAK3 expression and activation in human B cells and B cell malignancies

Members of the Janus family (JAK) of protein tyrosine kinases are critical enzymes in signaling pathways via hematopoietin receptors. We have cloned JAK3, which unlike other known family members (JAK1, JAK2, and TYK2) is preferentially expressed in hematopoietic cells but not in a variety of other cells. Functionally, JAK3 and JAK1 are coupled to the receptors for IL-2, IL-4, IL-7, IL-9, and IL-15 in T cells and NK cells. Because of the importance of IL-2, IL-4, and IL-7 in B cell physiology, we sought to determine whether JAK3 was also present in B lymphocytes and whether it was involved in signaling via cytokines that are important for B cell development and function. In this report, we demonstrate that JAK3 is expressed in normal human peripheral blood B cells at levels that are comparable to those in T cells. In addition, the levels were found to be markedly up-regulated following stimulation with staphylococcal protein A Cowan and anti-CD40 Abs. In addition, IL-4 and IL-7 induced the rapid tyrosine phosphorylation of JAK3 and JAK1, and IL-4 activated both JAK3 and JAK1 phosphotransferase activity. JAK3 protein was also detected in immature B cell lines, but not in more well differentiated cell lines. Additionally, JAK3 was detected in lysates from bone marrow lymphoblasts of patients with B cell precursor acute lymphocytic leukemia and cell lines derived from human B cell lymphomas. Together, these data suggest that the regulation of JAK3 expression and activity is likely to be important in B cell development and function.

Regulation of JAK3 expression and activation in human B cells and B cell malignancies

Members of the Janus family (JAK) of protein tyrosine kinases are critical enzymes in signaling pathways via hematopoietin receptors. We have cloned JAK3, which unlike other known family members (JAK1, JAK2, and TYK2) is preferentially expressed in hematopoietic cells but not in a variety of other cells. Functionally, JAK3 and JAK1 are coupled to the receptors for IL-2, IL-4, IL-7, IL-9, and IL-15 in T cells and NK cells. Because of the importance of IL-2, IL-4, and IL-7 in B cell physiology, we sought to determine whether JAK3 was also present in B lymphocytes and whether it was involved in signaling via cytokines that are important for B cell development and function. In this report, we demonstrate that JAK3 is expressed in normal human peripheral blood B cells at levels that are comparable to those in T cells. In addition, the levels were found to be markedly up-regulated following stimulation with staphylococcal protein A Cowan and anti-CD40 Abs. In addition, IL-4 and IL-7 induced the rapid tyrosine phosphorylation of JAK3 and JAK1, and IL-4 activated both JAK3 and JAK1 phosphotransferase activity. JAK3 protein was also detected in immature B cell lines, but not in more well differentiated cell lines. Additionally, JAK3 was detected in lysates from bone marrow lymphoblasts of patients with B cell precursor acute lymphocytic leukemia and cell lines derived from human B cell lymphomas. Together, these data suggest that the regulation of JAK3 expression and activity is likely to be important in B cell development and function.

[The attitude and vaccination practice of a sample of Campania pediatricians]

One hundred-twenty-six pediatricians were questioned about their attitudes concerning the practice of immunization, their feelings about the new vaccines (measles, mumps, german measles, hepatitis b) and about the pertussis vaccine. 80% of them reported that indications and contraindications were still unclear: Down's syndrome and atopic eczema are still thought to be real contraindications--despite the mass of papers suggesting that they are not so--, moreover 95% of the participants persists into the unnecessary evaluation of the antibody title following hepatitis b immunization. We conclude that it would be wise to periodically diffuse to pediatricians update recommendations about the extended immunization program, especially in our region, were still an high number of children are not properly immunized.

Psychosocial factors and recurrent genital herpes: a review of prediction and psychiatric treatment studies

OBJECTIVE

The purpose of this review was to evaluate the evidence which supports the association between psychosocial factors and genital herpes simplex virus recurrences (HSV), as well as to examine the biological and psychological treatments for disease.

METHOD

Forty-five studies were reviewed from the years 1928 to 1991. Studies were identified via computerized biographic literature search of Psychological Abstracts and Medline. Additional studies were located by inspection of key article reference sections. Studies were included in the review if the sample consisted of recurrent genital herpes sufferers and the design was either correlational or experimental. Cases studies were reviewed if they described HSV psychiatric treatment and provided outcome information.

RESULTS

Psychosocial variables are important elements in the prediction, maintenance, and management of recurrent genital herpes. Furthermore, the effectiveness of psychological treatment regimes may be explained via psychoimmunological theory.

CONCLUSIONS

Psychosocial treatment should be considered as adjunctive therapy for biological treatment of recurrent HSV infections. Future research should address primary prevention of genital herpes and other sexually transmitted diseases, including HIV infections.

A prospective randomized trial comparing the infectious and noninfectious complications of an externalized catheter versus a subcutaneously implanted device in cancer patients

PURPOSE

To compare the frequency of infectious episodes or other problems occurring with an externalized catheter (Hickman) versus a subcutaneously implanted device (Port-a-Cath, Pharmacia, Piscataway, NJ) in cancer patients, we performed a prospective, randomized study in 100 cancer patients (age range, 5 to 74 years).

PATIENTS AND METHODS

Patients who were chemotherapy candidates and required an indwelling catheter were monitored prospectively and evaluated during the 180 days after the insertion of the catheter and again at time of study closure. The frequency of catheter use, reason for access, and any problems that might have been related to catheter use were noted. All data were collected prospectively and included the patient's age, sex, underlying malignancy, temperature, and leukocyte and absolute granulocyte counts at the time of catheter insertion and when complications occurred. The time to and reason for removal of the catheter, as well as any intercurrent infectious or mechanical problems, were also determined.

RESULTS

Most of the infections that occurred were caused by gram-positive organisms, especially staphylococci or streptococci. A total of 22 complications (11 in each group) resulted in removal of the central line. Only one infection in the Hickman catheter group and four in the Port-a-Cath group led to removal of the central line. All other infectious episodes were successfully treated without removal of the catheters. The mean device life was 230 days for the Hickman catheter and 318 days for the Port-a-Cath (not significant).

CONCLUSION

There were no differences between the two study groups regarding incidence of documented infections or mechanical or thrombotic complications.