Understanding limb necrotizing infections: A comprehensive approach

INTRODUCTION

Necrotizing soft tissue infections (NSTI) are increasing, posing a significant risk of morbidity and mortality. Due to nonspecific symptoms, a high index of suspicion is crucial. Treatment involves a multidisciplinary approach, with broad-spectrum antibiotics, early surgical debridement, and life support. This study analyzes the characteristics, demographics, complications, and treatment of NSTI in a hospital in Madrid, Spain.

METHODS

A retrospective observational study was conducted, including all surgically treated NSTI patients at our center from January 2016 to December 2022, examining epidemiological and clinical data. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) was prospectively calculated for all patients.

RESULTS

Twenty-two patients (16 men, 6 women, mean age 54.8) were included. Median time from symptom onset to emergency room visit was 3.5 days. All reported severe treatment-resistant pain; sixteen had fever exceeding 37.8°C (72.7%). Skin lesions occurred in twelve (54.5%), and thirteen had hypotension and tachycardia (59.1%). Treatment involved resuscitative support, antibiotherapy, and radical debridement. Median time to surgery was 8.25h. Intraoperative cultures were positive in twenty patients: twelve Streptococcus pyogenes, four Staphylococcus aureus, one Escherichia coli, and four polymicrobial infection. In-hospital mortality rate was 22.73%.

CONCLUSIONS

We examined the correlation between our results, amputation rates and mortality with LRINEC score and time to surgery. However, we found no significant relationship unlike some other studies. Nevertheless, a multidisciplinary approach with radical debridement and antibiotic therapy remains the treatment cornerstone. Our hospital stays, outcomes and mortality rates align with our literature review, confirming high morbimortality despite early and appropriate intervention.

[Translated article] Clinical results of total hip arthroplasty assisted by robotic arm in Spain: Preliminary study

OBJECTIVES

Clinical, radiological and functional results of the first Spanish series of patients undergoing total hip arthroplasty assisted by Mako® (Stryker) robotic arm at the Hospital Clínico San Carlos (HCSC) in Madrid.

MATERIAL AND METHODS

Prospective and descriptive study analyzing the first 25 patients who underwent robotic-assisted THA at the HCSC, with a minimum follow-up of 4 months. Demographics, imaging studies (Mako® processing, Rx and CT), clinical parameters, functionality (modified Harris) and associated complications were evaluated.

RESULTS

Average age was 67.2 years (min 47, max 88), being 56% male population sample. 88% involves primary coxarthrosis, 4% post-traumatic coxarthrosis, 4% secondary avascular necrosis and 4% secondary femoroacetabular impingement. Average surgery time was 116.9min (min 92, max 150). The average time of the first five surgeries was 122.6min, and, regarding the last five interventions, it was 108.2min. Found medical intraoperative complications were four intraoperative markers loss. Average admission time was 4.4days (min 3, max 7), with an average postoperative haemoglobin decrease of 3.08±1.08g/dl, requiring a transfusion in 12% of the cases. Three medical complications have been registered in the meantime of the admission, with a relevant case of a confusional syndrome and a fall, which resulted in a non-displaced AG1 periprosthetic fracture. The analysis of the positioning of registered implants with Mako® system shows 40.55±1.53 acetabular inclination degrees and 12.2±3.6 acetabular anteversion degrees. The postoperative image study carried out on patients, are consistent with Mako® results, as it shows an acetabular inclination of 41.2±1.7 in Rx, as well as acetabular anteversion of 16±4.6 in CT. Hip length variance ranges depending on preoperative values of 3.91mm (SD: 3.9; min -12, max 3) to 1.29mm (SD: 1.96) after surgery registered with Mako®, with an increase of an average hip length of 5.64mm (SD: 3.35). Rx simple study results show a postoperative difference between both hips of 0.5±3.08mm, which is consistent with Mako® results. Native femoral offset was stable after surgery with a showing difference both pre and post operative of the intervened hip of 0.1mm (SD: 3.7), registered with Mako®. Preoperatory modified Harris punctuation was 41.6±13.3, improving to postoperative values of 74.6±9.7 after four months since the surgery. No complications were registered in immediate postoperative (4 months).

CONCLUSIONS

Total hip arthroplasty robot-assisted achieves an adequate precision and repeatability of the implant positioning and the postoperative hip dysmetry without showing an increase of associated complications to the technique applied. Surgery time, complications and functional results in a short-time period are similar to conventional techniques applied to great series previously published.

Clinical results of total hip arthroplasty assisted by robotic arm in Spain: Preliminary study

OBJECTIVES

Clinical, radiological and functional results of the first Spanish series of patients undergoing total hip arthroplasty assisted by Mako® (Stryker) robotic arm at the Hospital Clínico San Carlos (HCSC) in Madrid.

MATERIAL AND METHODS

Prospective and descriptive study analyzing the first 25 patients who underwent robotic-assisted THA at the HCSC, with a minimum follow-up of 4months. Demographics, imaging studies (Mako® processing, Rx and CT), clinical parameters, functionality (modified Harris) and associated complications were evaluated.

RESULTS

Average age was 67.2years (min 47, max 88), being 56% male population sample. 88% involves primary coxarthrosis, 4% post-traumatic coxarthrosis, 4% secondary avascular necrosis and 4% secondary femoroacetabular impingement. Average surgery time was 116.9min (min 92, max 150). The average time of the first five surgeries was 122.6min, and, regarding the last five interventions, it was 108.2min. Found medical intraoperative complications were four intraoperative markers loss. Average admission time was 4.4days (min 3, max 7), with an average postoperative hemoglobin decrease of 3.08±1.08g/dL, requiring a transfusion in 12% of the cases. Three medical complications have been registered in the meantime of the admission, with a relevant case of a confusional syndrome and a fall, which resulted in a non-displaced AG1 periprosthetic fracture. The analysis of the positioning of registered implants with Mako® system shows 40.55±1.53 acetabular inclination degrees and 12.2±3.6 acetabular anteversion degrees. The postoperative image study carried out on patients, are consistent with Mako® s results, as it shows an acetabular inclination of 41.2±1.7 in Rx, as well as acetabular anteversion of 16±4.6 in CT. Hip length variance ranges depending on preoperative values of 3.91mm (SD: 3.9; min -12, max 3) to 1.29mm (SD: 1.96) after surgery registered with Mako®, with an increase of an average hip length of 5.64mm (SD: 3.35). Rx simple study results show a postoperative difference between both hips of 0.5±3.08mm, which is consistent with Mako® results. Native femoral offset was stable after surgery with a showing difference both pre and post operative of the intervened hip of 0.1mm (SD: 3.7), registered with Mako®. Preoperatory modified Harris punctuation was 41.6±13.3, improving to postoperative values of 74.6±9.7 after four months since the surgery. No complications were registered in immediate postoperative (4month).

CONCLUSIONS

Total hip arthroplasty robot-assisted achieves an adequate precision and repeatability of the implant positioning and the postoperative hip dysmetry without showing an increase of associated complications to the technique applied. Surgery time, complications and functional results in a short-time period are similar to conventional techniques applied to great series previously published.

Simultaneous bilateral extracapsular proximal femur fractures in the elderly. A case report

Simultaneous and bilateral proximal femoral fractures (PFF) are rare and have scarcely been reported in the literature. A case of a bilateral extracapsular PFF is herein presented. Besides, an exhaustive review of the literature was performed, analyzing the information of all previously reported cases.

An 81-year-old woman, who suffered a casual fall, was diagnosed with bilateral PFF consisting of both a subtrochanteric and an intertrochanteric fracture. She underwent concurrent intramedullary fixation for both fractures without any relevant complication and started early ambulation. Simultaneous bilateral extracapsular PFF are exceptional, with only 23 cases described in the current literature. In the elderly, they deserve special attention with treatment strategies in between the ones for unilateral hip fractures and those provided to old multiply injured patients. PFF management is not well established. Minimal reaming and careful nailing can be safely performed bilaterally under close monitoring, in order to start an early functional recovery.

Fracture planning is easy: Development of a basic method of digital planning based on the traditional pencil and paper technique

INTRODUCTION

Preoperative planning constitutes a fundamental tool in the management of fractures; however, its practical application is far from the desired, perhaps due to the absence of a basic and simple method, adapted to the current times. We describe a digital planning method, halfway between the traditional and the technological, which preserves its educational essence, allows the understanding of the fracture and the individualization of the osteosynthesis.

MATERIAL AND METHODS

After the initial analysis of the fracture and the patient's characteristics, different measurements are made on X-ray and CT images with a digital medical imaging software. These images are then copied into a presentation program (Microsoft® PowerPoint or Keynote ©Apple Inc.), in which the main fragments and fracture lines are traced with the computer pointer. These are subsequently moved into a reduced position and the implants for internal fixation are graphically represented together with a guide of the surgical strategy.

RESULTS

We show 4 cases of different types of fractures operated through reduction and osteosynthesis after preoperative planning according to the described method. The basic points for the surgical planning, logistics, tactics and postoperative radiological results of each case are detailed.

CONCLUSIONS

Despite rise of advanced planning software, traditional paper and pencil methods are still fundamental, even more so for the trauma surgeon in training. The digital planning method described is very appropriate for this purpose, as it combines the advantages of both methods: simplicity, accessibility, quickness, low-cost, reproducibility, educational character, efficiency and possibility of simulation, corrections and reuse of cases.

Renunciations in forefoot surgery. Critical analysis of surgical waiting lists

INTRODUCTION

The high prevalence of forefoot pathology generates long surgical waiting lists (SWL). We have detected a considerable number of patients who withdraw surgery, which creates an important distortion in our activity and high expenditure of resources. Our objective is to study the factors related to these resignations, as well as, compare them with other pathologies of high prevalence and ambulatory surgical treatment: carpal tunnel syndrome (CTS) and internal meniscopathy (IM).

MATERIAL AND METHODS

Retrospective study of the surgical cancellations on 2,399 patients included in the SWL of the Foot and Ankle Unit of our center for forefoot surgery, between January/2014 and March/2018, both included.

RESULTS

We have found 389 renunciations, which represent 16.22% of the inclusions in SWL, with 84.83% of women. The pathologies with the highest rate of resignation have been Morton metatarsalgia (24%) and hallux rigidus (20.16%). The most frequent pathology, hallux valgus, records 15.96% of resignations that occur mostly between 6 and 9 months. In the CTS and IM, the resignation rate has been 17.42 and 8.92%, respectively, with higher resignation rates in the first 3 months.

CONCLUSIONS

The withdrawal of a scheduled intervention on the forefoot registers a high frequency in our environment, which can be related to factors such as the type of pathology, its natural history, response to orthopedic interventions, time in LEQ, and other non-specific ones on which we must investigate, to rationalize and establish duties in our SWL.

[Relationship between previous severity of illness and outcome of in-hospital cardiac arrest]

OBJECTIVES

To analyze the relationship between previous severity of illness, lactic acid, creatinine and inotropic index with mortality of in-hospital cardiac arrest (CA) in children, and the value of a prognostic index designed for adults.

METHODS

The study included total of 44 children aged from 1 month to 18 years old who suffered a cardiac arrest while in hospital. The relationship between previous severity of illness scores (PRIMS and PELOD), lactic acid, creatinine, treatment with vasoactive drugs, inotropic index with return of spontaneous circulation and survival at hospital discharge was analyzed.

RESULTS

The large majority (90.3%) of patients had a return of spontaneous circulation, and 59% survived at hospital discharge. More than two-thirds (68.2%) were treated with inotropic drugs at the time of the CA. The patients who died had a higher lactic acid before the CA (3.4 mmol/L) than survivors (1.4 mmol/L), P=.04. There were no significant differences in PRIMS, PELOD, creatinine, inotropic drugs, and inotropic index before CA between patients who died and survivors.

CONCLUSION

A high lactic acid previous to cardiac arrest could be a prognostic factor of in-hospital cardiac arrest in children.

HEY1 Leu94Met gene polymorphism dramatically modifies its biological functions

The hairy/enhancer-of-split related with YRPW motif 1 (HEY1) is a member of the basic-helix-loop-helix-Orange (bHLH-O) family of transcriptional repressors that mediate Notch signaling. Several cancer-related pathways also regulate HEY1 expression, and HEY1 itself acts as an indirect positive regulator of the p53 tumor suppressor protein and a negative regulator of androgen receptor activity. In this study we show how a naturally occurring non-synonymous polymorphism at codon 94 of HEY1, which results in a substitution of leucine by methionine (Leu94Met), converts HEY1 from an androgen receptor corepressor to an androgen receptor co-activator without affecting its intrinsic transcriptional repressive domains. The polymorphism Leu94Met also abolishes HEY1-mediated activation of p53 and suppresses the ability of HEY1 to induce p53-dependent cell-cycle arrest and aberrant cell differentiation in human osteosarcoma U2OS cells. Moreover, expression of HEY1, but not of the variant Leu94Met, confers sensitivity to p53-activating chemotherapeutic drugs on U2OS cells. In addition, we have identified motifs in HEY1 that are critical for the regulation of its subcellular localization and analysed how mutations in those motifs affect both HEY1 and HEY1-Leu94Met functions. These findings suggest that the polymorphism Leu94Met in HEY1 radically alters its biological activities and may affect oncogenic processes.

Binding to nucleophosmin determines the localization of human and chicken ARF but not its impact on p53

The ARF tumour suppressor gene encodes a small highly basic protein whose known functions are largely determined by the amino acids encoded within the first exon. In mammals, the protein incorporates additional residues specified by an alternative reading frame in the second exon of INK4a, but this arrangement does not apply to the chicken homologue. In exploring the intracellular localization of chicken p7(ARF), we found that while the FLAG- and HA-tagged versions localize in the nucleolus, in line with mammalian ARF, the GFP-tagged version is excluded from the nucleolus. Here we show that irrespective of the source or composition of the ARF fusion proteins, versions that accumulate in the nucleolus share the ability to bind to nucleophosmin (NPM). Depletion of NPM with siRNA results in the re-location and destabilization of nucleolar forms of ARF but has little effect on the location or stability of a nucleoplasmic form of ARF. Importantly, knockdown of endogenous NPM does not impair the ability of ARF to bind to MDM2 and stabilize p53. These findings support the view that nucleolar localization determines the stability of ARF but not its primary function.

Effectiveness of negative pressure closure in the integration of split thickness skin grafts: a randomized, double-masked, controlled trial

OBJECTIVES

To determine the effectiveness of the negative pressure closure (NPC) technique in the integration of split-thickness skin grafts (STSG) to the recipient site.

METHODS

Randomized, double-masked, controlled trial.

SETTING

A tertiary burn unit.

PATIENT CHARACTERISTICS

Between May 2003 and October 2004, 60 patients having wounds with skin loss which hindered primary closure, were incorporated to this study. We excluded patients with > or =20% of total body surface burns, polytraumatized, surgical contraindications, those who were enlisted in other clinical trials, and those who rejected the informed consent.

INTERVENTIONS

In all the patients, surgical cleaning of the recipient site and STSG were performed after which they were randomly assigned between 2 groups: a group that received a NPC dressing and were connected to the central aspiration system at -80 mm Hg versus a control group with similar dressing but without connection to negative pressure. Loss of STSG area at the fourth postoperative day, days of hospital stay.

RESULTS

Sixty patients were included. The median loss of the STSG in the NPC group was 0.0 cm versus 4.5 cm in the control group (P = 0.001). The median hospital stay was of 13.5 days in the NPC group versus 17 days in the control group (P < 0.001).

CONCLUSIONS

The use of NPC significantly diminishes the loss of STSG area, as well as shortens the days of hospital stay. Therefore, it should be routinely used for these kinds of procedures.

Residue levels of captan and trichlorfon in field-treated kaki fruits, individual versus composite samples, and after household processing

The dissipation of residue levels of captan and trichlorfon in field-treated kaki crops was studied according to good laboratory practices to propose maximum residue limits (MRLs). Residue levels of captan and trichlorfon were analysed by GC/MS and LC-MS/MS, respectively. Residue levels of captan and trichlorfon permitted one to propose MRLs in kaki of 3 and 5 mg kg(-1), respectively. The behaviour of these residues was also studied after peeling and cooking, and in individual fruits versus composite samples. Residue levels of these compounds for individual fruits suggested that a variability factor up to three could be set for the acute risk assessment. Levels of captan decreased by more than 90% after peeling and completely after cooking. Trichlorfon penetrates into the flesh in a proportion of 70% of the residue at the pre-harvest interval. Cooking resulted in a decrease of 27% of residue levels of trichlorfon.

Concordance between qualitative and quantitative cultures in burned patients

OBJECTIVE

To determine the concordance between superficial cultures (SC) and quantitative cultures (QC) in the diagnosis of wound infection in burn patients.

METHOD

SAMPLE

All SC and QC taken from the same patient, site and during the same surgery were analysed.

VARIABLES

On the SC, the microorganism (MO) and its amount defined subjectively by the microbiologist was recorded (negative, very low, low, regular and abundant). On the QC, the MO and its amount were expressed as colony forming units per gram of tissue (CFUs/g).

STATISTICS

Kappa index of agreement beyond chance; Wilcoxon and Kruskall-Wallis for continuous variables and chi(2) for categorical variables were used with a p<0.05 indicating statistical significance.

RESULTS

One thousand four hundred and forty three pairs of cultures were analyzed. The concordance between SC and QC (Kappa index) was 52%. On the SC, only when the microbiologist subjectively informed "abundant" MOs there was a significant difference (p<0.0001). There were 6.1% of QCs with more than 10(5) CFUs/g and the most frequent MOs isolated were: S. aureus (27.9%), E. coli (11.6%), P. aeruginosa (11.6%), E. faecalis (11.6%) and S. epidermidis (7.0%).

CONCLUSIONS

SC has a moderate concordance with the QC showing a low reliability between the two methods. The subjective information given by the microbiology technician in the SC is not precise. A study in which the two methods be compared blindly against the reference standard, in a prospective cohort of patients, it is needed to discriminate which of two methods it is the most accurate one determining sensitivity and specificity.

ASPP1 and ASPP2 are new transcriptional targets of E2F

The E2F family of transcription factors regulates the expression of a number of genes whose products are involved in cell cycle control, DNA replication and apoptosis. We show here that E2F-1 binds in vivo the promoters of ASPP1 and ASPP2 genes, two activators of p53-mediated apoptosis, E2F-1, E2F-2 and E2F-3 all activate the isolated ASPP1 and ASPP2 promoters. Overexpression or deregulation of E2F-1 increased the expression levels of ASPP1 and ASPP2 mRNA and proteins. The identification of ASPP1 and ASPP2 genes as transcriptional targets of E2F provides another mechanism by which E2F cooperates with p53 to induce apoptosis.

Stabilization of p53 by p14ARF without relocation of MDM2 to the nucleolus

The alternative product of the human INK4a/ARF locus, p14ARF, has the potential to act as a tumour suppressor by binding to and inhibiting the p53 antagonist MDM2. Current models propose that ARF function depends on its ability to sequester MDM2 in the nucleolus. Here we describe situations in which stabilization of MDM2 and p53 occur without relocalization of endogenous MDM2 from the nucleoplasm. Conversely, forms of ARF that do not accumulate in the nucleolus retain the capacity to stabilize MDM2 and p53. We therefore propose that nucleolar localization is not essential for ARF function but may enhance the availability of ARF to inhibit MDM2.

The c-erbA alpha protooncogene induces apoptosis in glial cells via a protein kinase C- and bcl-2-suppressible mechanism

The c-erbA protooncogene encodes the thyroid hormone (3,5,3'-triiodothyronine; T3) receptor alpha1 (TR alpha1). c-erbA/TR alpha1 is expressed in many cell types including glial cells, particularly in the immature state. We show here by morphological and biochemical criteria that c-erbA induces apoptosis of glial B3.1 cells in serum-deprived conditions. This effect is mostly T3 independent. Growth factors such as platelet-derived growth factor, basic fibroblast growth factor, or transforming growth factor-alpha prevent B3.1 + TR alpha1 cell death. Protein kinase C (PKC) activators also prevent the apoptosis phenomenon, an effect that was blocked by the PKC-specific inhibitor GF109203X. Expression of an exogenous bcl-2 gene led also to B3.1 + TR alpha1 cell survival. Neither a series of inhibitors including GF109203X nor T3 inhibits bcl-2 action, indicating that bcl-2 blocks a downstream step in the death-promoting process. B3.1 + TR alpha1 cell apoptosis is not blocked by caspase-1 or poly-ADP-ribosyltransferase inhibitors, suggesting that the activation of these classic pathways is not involved in the apoptotic mechanism. In addition, direct interaction with specific neuronal cells but not incubation with their conditioned medium inhibits also apoptosis of B3.1 + TR alpha1 cells. Our results show that c-erbA promotes an apoptotic process in glial B3.1 cells that is suppressible by PKC activation and bcl-2, probably by distinct mechanisms.

v-erbA oncogene induces invasiveness and anchorage-independent growth in cultured glial cells by mechanisms involving platelet-derived growth factor

The v-erbA oncogene coding for a mutated form of the thyroid hormone (T3) receptor (TR alpha 1) increased the invasion capacity of the mouse B3.1 glial cell line. This effect was mediated by the induction of platelet-derived growth factor (c-sis/PDGF B), as shown by its inhibition using an anti-PDGF BB antibody. Also, the low invasion capacity of parental B3.1 and c-erbA-expressing cells (B3.1 + TR alpha 1) was enhanced by exogenously added PDGF BB. This effect was independent of the growth-promoting activity of PDGF and unrelated to the secretion of metalloproteinases. All three cell types (parental B3.1, B3.1 + v-erbA, and B3.1 + TR alpha 1) secreted similar high levels of the M(r) 72,000 collagenase IV (A) independently of PDGF. Anchorage-independent cell growth was also enhanced by v-erbA; B3.1 + v-erbA cells but neither parental B3.1 nor B3.1 + TR alpha 1 cells formed foci in soft agar. The effect of v-erbA only happened in the presence of serum, suggesting that some serum factor(s) cooperate with PDGF to overcome the anchorage dependence of B3.1 + v-erbA cells. Supporting this, high doses of exogenous PDGF were much less efficient than serum, and the addition of an anti-PDGF BB antibody blocked only partially the effect of serum. Basic fibroblast growth factor was found to cooperate with PDGF to abolish anchorage dependence. Moreover, B3.1 + v-erbA cells detached and grew in suspension when cultured on plastic dishes. Interestingly, the transformation-competent c-jun and fra-1 oncogenes were induced by v-erbA in serum-free medium and are candidates to mediate v-erbA effects. In summary, our results show that v-erbA induces transformation parameters in the glial B3.1 cell line via an increase in c-sis/PDGF B and probably other mechanisms, suggesting a role for (autocrine) PDGF stimulation in glial cell transformation.

Induction of platelet-derived growth factor B/c-sis by the v-erbA oncogene in glial cells

The v-erbA oncogene codes for a mutated form of the thyroid hormone receptor TR/c-erbA-alpha. Thyroid hormone (triiodothyronine, T3) regulates glial functions such as myelination and both astrocytes and oligodendrocytes have been shown to express thyroid hormone receptors (TRs). To study putative effects of v-erbA on glial precursors, we have expressed it in a glial clonal cell line established from early embryonal mouse brain. We have found that v-erbA increases cell survival in serum-free conditions. Moreover, v-erbA-expressing cells show a substantial growth in the presence of insulin or IGF-I, whereas normal and TR/c-erbA-over-expressing cells progressively degenerate. By Northern blotting, immunofluorescence, immunoprecipitation, and neutralization experiments, we show that v-erbA actions are mediated by an increase in the levels of PDGF B/c-sis mRNA and protein. We used anti-PDGF receptor and anti-phosphotyrosine antibodies to show the constitutive activation of PDGF receptors in B3.1 + v-erbA cells, and neutralizing anti-PDGF antibodies to demonstrate that v-erbA enhances the secretion of active PDGF into the culture medium. Our data indicate that v-erbA induces PDGF B/c-sis, a factor involved in the generation of gliomas, the most common central nervous system tumor in humans.

c-erbA and v-erbA modulate growth and gene expression of a mouse glial precursor cell line

The c-erbA alpha protooncogene coding for the thyroid hormone (T3) receptor (TR alpha 1) and the viral, mutated v-erbA oncogene were expressed in an immortal mouse glial cell line (B3.1) using retroviral vectors. c-erbA alpha expression led to a decrease in cell proliferation in high and low serum conditions, both in the presence and in the absence of T3. In serum-free medium, c-erbA-expressing cells (B3.1 + TR alpha 1) were completely arrested, whereas cells expressing v-erbA (B3.1 + v-erbA) showed a higher DNA synthesis rate than normal B3.1 cells. Although proliferation of all three cell types was stimulated by platelet-derived growth factor and basic fibroblast growth factor, differences were also observed in the response to these agents. B3.1 + TR alpha 1 cells were more sensitive to platelet-derived growth factor than B3.1 and B3.1 + v-erbA cells. In contrast, B3.1 cells responded to basic fibroblast growth factor better than B3.1 + TR alpha 1 or B3.1 + v-erbA cells. Insulin-like growth factor I potentiated the action of platelet-derived growth factor and basic fibroblast growth factor. Again, different responses to treatment with insulin-like growth factor I alone were observed; B3.1 + TR alpha 1 cells did not respond to it, whereas B3.1 + v-erbA cells showed a dramatic stimulation by this agent. Interestingly, in the presence of T3, the blockade in B3.1 + TR alpha 1 cell proliferation was accompanied by the down-regulation of the typical astrocytic genes, glial fibrillary acidic protein and vimentin. These hormone effects were not found in v-erbA-expressing cells. In addition, v-erbA inhibited the basal expression of the cyclic nucleotide phosphodiesterase gene, an oligodendrocytic marker.(ABSTRACT TRUNCATED AT 250 WORDS)

The value of the echo-Doppler in cardiomyoplasty procedures

Echo-Doppler determinations were performed in patients submitted to cardiomyoplasty procedure using the latissimus dorsi muscle graft (LDMG). In four patients who had 1 year of follow-up or more the left ventricular internal dimension in diastole (LVIDd), left ventricular internal dimension in systole (LVIDs), septal-E point separation (E-septum), distance of the mitral valve (E-E'), maximal aortic cuspid separation (MACS) and left atrium dimension (LA) were determined by two-dimensional echocardiogram. With a pulsed Doppler in the aortic root the following parameters were obtained: aortic peak flow (AoPF), velocity time integral (VTI), and ejection period (EP). With the stimulator on, the determinations were done using a ventricle muscle (VM) delay of 25, 75, and 250 msec.

RESULTS

No significant differences were observed by Echo determinations between the stimulator off and on. With the supporting contraction of the LDMG the best hemodynamic performance was obtained when the VM delay ranged between 75 and 250 msec. Values with the stimulator off and on were as follows: AoPF: 90.8 +/- 8 cm/sec and 104.5 +/- 9 cm/sec; VTI: 14.8 +/- 2 cm and 19.2 +/- 2 cm; EP: 230 +/- 10 msec and 245 +/- 20 msec. A decrease in the systolic pressure of the pulmonary artery and a decreased functional regurgitation of the mitral and tricuspid valve were observed in the follow-up determinations. All patients showed restricted mitral flows that remained unchanged during the follow-up.

CONCLUSIONS

In this group of patients the echo-Doppler showed an improvement of the systolic function of the left ventricle when it is supported by the LDMG.(ABSTRACT TRUNCATED AT 250 WORDS)