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C Esposito

Publications and source records attributed to C Esposito.

At least 73 records · Page 4Linked to original sources
PubMed1999

Nature and severity of the glomerular response to nephron reduction is strain-dependent in mice.

Nephron reduction is an important factor in the development of glomerulosclerosis. In a study of the oligosyndactyly (Os) mutation that causes a congenital 50% reduction in nephron number, we previously found that ROP Os/+ mice developed glomerulosclerosis whereas C57B1/6J Os/+ mice did not. We concluded that the predisposition to glomerulosclerosis depended largely on the genetic background, the ROP being sclerosis-prone whereas the C57 strain was sclerosis-resistant. In the current experiments we asked whether the intensity of the sclerotic response to nephron reduction in the ROP strain was related to the time at which it occurred, ie, a pre- or post-natal event. We also determined whether the absence of lesions in C57 Os/+ mice was caused by a higher threshold for the induction of a sclerotic response in C57 mice. We further examined the relationship between glomerular hypertrophy and sclerosis. C57 +/+, C57 Os/+, ROP +/+, and ROP Os/+ mice were uninephrectomized (NX) at age 10 weeks and followed for 8 weeks. We found no sclerotic changes in NX C57 +/+ and C57 Os/+ mice, despite a 75% reduction in nephron number in the latter. In contrast, both NX ROP +/+ and NX ROP Os/+ mice had glomerulosclerosis, which was more severe in the NX ROP Os/+ mice. Examination of extracellular matrix synthesis and degradation at the mRNA level revealed that synthesis exceeded degradation in ROP Os/+ mice. The lesions in NX ROP +/+ were less severe than in sham-operated ROP/Os mice, suggesting that the timing of nephron reduction affected the amplitude of the sclerotic response in this strain. Following NX, an increase in glomerular volume was found in C57 +/+, ROP +/+, and ROP Os/+ mice. However, NX did not lead to a further increase in glomerular volume in C57 Os/+ mice. We make three conclusions: 1) sclerosis was more severe in the ROP strain when nephron reduction occurred in utero; 2) the absence of glomerulosclerosis in C57 mice was not related to a higher threshold for a sclerosis response in this strain; and 3) whereas glomerular size continued to increase as nephron number decreased in ROP mice, it reached a plateau in C57 mice.

Animals↗
PubMed1999

Laparoscopic treatment of congenital inguinal hernia in children.

PURPOSE: The authors report their experience in the laparoscopic treatment of congenital inguinal hernia in children. METHODS: Between September 1994 and September 1995, 45 boys between 8 months and 13 years of age (mean, 4 years) were treated laparoscopically for hydroceles, spermatic cord cysts, or hernias. Twenty-six (57.8%) boys showed a right inguinal hernia, 17 (37.8%) a left hernia, and two cases (4.4%) presented the clinical data of a bilateral pathology. The approach used for small hernias was the placement of purse-string suture around the internal orifice of the inguinal canal (28 cases). As to hernias exceeding 4 to 5 mm in diameter, the external hemicircumference of the neck was opened to bring the conjoined tendon closer to the crural arch with a nonresorbable suture (17 cases). There was never need to use a prosthesis. RESULTS: Surgery lasted from 15 to 45 minutes with the duration decreasing with experience. There were no intra- or postsurgical complications. Two patients (4.4%) experienced a recurrent inguinal hernia, which was successfully operated on again with laparoscopy. CONCLUSION: The early results of these authors suggest that laparoscopic surgery is a feasible and safe technique for the treatment of patent peritoneal vaginal canal (PVC) and inguinal hernia in children.

Child↗
PubMed1999

Surgical anatomy of the mediastinum.

After a short description of mediastinal anatomy and embryology, the authors illustrate the division of the mediastinum, based on criteria of either surgical anatomy or radiological anatomy. Lastly, they discuss the topographical distribution of the mediastinal masses in anterior, visceral, and posterior compartments of the mediastinum.

Humans↗
PubMed1999

Enzymatic synthesis of vasoactive intestinal peptide analogs by transglutaminase.

Vasoactive intestinal peptide is an amino acceptor and donor substrate for tissue transglutaminase (TGase) in vitro. This peptide contains a single glutamine residue, Gln16, which was identified as the amino acceptor substrate. Different gamma(glutamyl16)amine derivatives of vasoactive intestinal peptide were synthesized enzymatically in vitro. The modification is very fast when compared with that of many native substrates of TGase. The analogs 1,3-diaminopropane, putrescine, cadaverine, spermidine, spermine, glycine ethyl ester and mono-dansylcadaverine of the peptide were purified by high-performance liquid chromatography on a reverse-phase column and were analyzed by electrospray mass spectrometry. When amines were absent in the assay mixture as an external amino donor, lysine residue occurring in the peptide was an effective amino donor site for TGase. Only one of the three lysine residues of vasoactive intestinal peptide, namely Lys21, was demonstrated to be involved in both inter- and intramolecular cross-link formation.

Amines↗
PubMed1999

[Vascular complications during laparoscopy. An analysis of a personal case].

Vascular complications of laparoscopy most often occur during Veress needle or primary trocar placement. Veress needle punctures are insignificant and require no further treatment, whereas trocar induced vascular injuries can be catastrophic. The frequency of vascular or viscus injuries is difficult to calculate since several complications are not published. A vascular complication occurred in a young girl with neurologic problems and a kyphoscoliosis operated on in laparoscopy for a gastroesophageal reflux is discussed. After the establishment of pneumoperitoneum, an important hemoperitoneum was rapidly evident at insertion of the laparoscope. An open laparotomy was performed showing right common iliac vessel injuries and several intestinal perforations. After a complex vascular reconstruction and a multiple intestinal suture, the Nissen fundoplication with pyloroplasty was performed traditionally and the patient leave the hospital free of symptoms after 20 days. In laparoscopy, as in all areas of surgery, experience knowledge and meticulous attention to details are the most important factors in order to avoid complications. The authors believe that the open approach with Hasson cannula is the most important factor in avoiding complications.

Child, Preschool↗
PubMed1998

PAX 8 activates the enhancer of the human thyroperoxidase gene.

In this study we report on a novel natural target of the paired domain transcription factor PAX 8 in the enhancer element of the human thyroperoxidase gene, one of the most important thyroid differentiation markers. It is the primary enzyme involved in thyroid hormone synthesis and PAX 8 has been previously identified as an activating factor of the rat thyroperoxidase gene promoter. In vitro, PAX 8 binds a cis element of the human enhancer and its exogenous expression induces the enhancer activity in co-transfection experiments in Cos-7 cells. When mutated at this binding site, the enhancer is no longer activated by PAX 8. Our finding strengthens the PAX 8 role in the maintenance of thyroid differentiation and in particular in the tissue-specific thyroperoxidase gene expression.

Animals↗
PubMed1998

Cell membrane lipid molecular dynamics in a solenoid versus a magnetically shielded room.

The generalized polarization function of the fluorescent probe 2-dimethylamino-6-lauroylnaphthalene has been used to evaluate the lipid dynamics in Friend erythroleukemia cell membrane. The values of this function varied during the culture growth cycle, showing decreased lipid dynamics 24-48 h from the cell seeding. When the cycle occurred in a solenoid producing a magnetic field of 70 microT at 50 Hz in addition to the 45 microT DC of the earth (short-term 4-day exposure), the membrane lipid dynamics during this same time-period decreased by about 10% (P < .04). After long-term (184 days) or extremely long-term (395 days) exposure of the cells to the magnetic field, little additional variation in the membrane lipid dynamics was observed, suggesting an adaptation phenomenon. A variation of membrane lipid dynamics was also observed due to in vitro cell differentiation (P < .02). Nevertheless, the exposure of both undifferentiating and differentiating cells to a highly attenuated magnetic field in a magnetically shielded room (20 nT DC plus 2.5 pT AC) did not induce any modification of membrane lipid dynamics.

Animals↗
PubMed1998

The use of laparoscopy in the diagnosis and treatment of abdominal complications of ventriculo-peritoneal shunts in children.

Ventriculo-peritoneal shunts (VPS) are the most frequent operative procedures used to treat hydrocephalic children. Abdominal complications of VPS are now a rare event; however, their frequency varies from 5% to 47% according to reports. Anything that causes an obstruction or impediment of the VP derivation system will lead to intracranial hypertension, which requires immediate surgery. From 1985 to 1995 at the Division of Pediatric Surgery of the Federico II University of Naples, ten laparoscopies were performed in ten children with VPS complications. Cerebrospinal fluid pseudocysts were found in four infants. There was one case of abdominal wall perforation by the tip of the catheter at the umbilical level, two bowel obstructions, and one catheter was lost in the abdominal cavity. Finally, two children had malfunctioning of the peritoneal limb of the catheter. The laparoscopic technique was curative in all ten cases, thus avoiding a conventional laparotomy and the consequent risk of adhesions, which could cause further complications.

Abdominal Injuries↗
PubMed1998

Congenital megalourethra associated with urethral duplication and imperforate anus.

A newborn with a prenatal diagnosis of right hydroureteronephrosis and enlarged penis is presented. At birth, the baby had an imperforate anus (IA) with a megalourethra; radiologic and ultrasonographic studies showed a left polycystic kidney and right hydroureteronephrosis, right vesicoureteral reflux, and an incomplete urethral duplication with dilatation of the posterior urethra. The IA was corrected on the 1st day of life and a vesicostomy was performed at 1 month. At 1 year of age the valve obstructing the ventral posterior urethra was resected and the vesicostomy was closed. At 14 months the baby underwent a urethroplasty with a vertical preputial tubularized island flap and excision of the penile urethral duplication. Exact knowledge of the malformation was essential in planning the appropriate surgical treatment.

Anus, Imperforate↗
PubMed1998

Laparoscopic treatment of recurrent inguinal hernia in children.

The authors report their experience with the laparoscopic treatment of recurrent inguinal hernia in children. Between April 1993 and January 1998, 225 boys aged 8 months to 14 years (mean 4.4 years) were treated laparoscopically for a hydrocele, spermatic-cord cyst, or hernia. Ten boys had recurrent inguinal hernias after conventional surgery, in one case bilateral. The technique requires 3 trocars: a 0 degrees, 5-mm telescope inserted through the umbilicus and two 3-mm trocars placed 3-4 cm below the umbilicus on either side. Simple patency of the peritoneal vaginal duct (dpv) was found in eight cases and a direct inguinal hernia in three. In cases with an open dpv, we opened the external hemicircumference of the neck in order to bring the conjoined tendon closer to the crural arch with a non-resorbable 4/0 suture, and then placed a 3/0 resorbable pursestring suture around the peritoneum of the internal orifice of the inguinal canal. In direct inguinal hernias the orifice was closed by placing 2-3 nonabsorbable 3/0 sutures between the two muscular sides of the hernial defect. There were no intra- or postsurgical complications. All patients, at a maximum follow-up of 3 years showed total recovery from the hernia. Our early results suggest that laparoscopic surgery is a feasible and safe technique for the treatment of recurrent inguinal hernia in children. Key words Recurrent inguinal hernia. Laparoscopy. Children

Adolescent↗
PubMed1998

One-trocar appendectomy in pediatric surgery.

Laparoscopic appendectomy is a safe alternative to open appendectomy to treat appendicitis. The author reports his experience in performing laparoscopic appendectomy with the use of only one trocar in pediatric patients. Between 1 January 1994 and 30 October 1995 at the Department of General and Pediatric Surgery, Division of Pediatric Surgery of the "Federico II" University of Naples, we performed 51 laparoscopic appendectomies. Patient age varied from 4 to 16 years with a mean age of 7 years. In the last 25 patients of our series we performed the one-trocar appendectomy, positioning only one trocar infraumbilically with the use of a 10-mm operative telescope. The appendix is identified, dissected when necessary, grasped laparoscopically with a 450-mm operative atraumatic instrument introduced through the operative channel of the laparoscope, and then exteriorized through the umbilical cannula. The appendectomy was performed using traditional method outside the abdominal cavity. We had no intra- or perioperative mortality or morbidity. The mean overall hospitalization time was 2 days (1-4 days). At a maximal follow-up of 20 months the children have no clinical problems nor any visible scar related to the laparoscopic appendectomy. In conclusion, the author considers the one-trocar appendectomy an appropriate alternative procedure to other techniques of laparoscopic appendectomy.

Acute Disease↗
PubMed1998

Laparoscopic management of ovarian cysts in newborns.

BACKGROUND: Cysts are the most common ovarian masses found in newborn girls. Spontaneous regression, which occurs in approximately 25-50% of cases, is more frequent with smaller cysts. Pre- or postnatal complications are common; these complications may consist of intracystic bleeding, torsion of the cyst or corresponding annex, or self-amputation of the cyst. When the cyst is <4 cm it is possible to perform a simple echographic monitoring to check for the possibility of spontaneous involution; all other cases require surgery. METHODS: Between February 1985 and June 1997, we treated 22 neonatal ovarian cysts laparoscopically. In 14 cases, the right side was involved; in eight cases, it was the left. The patients' ages ranged between 7 days and 5 months (median, 45 days). In all cases, we used three trocars. An intraperitoneal cystectomy was done in eight cases, a transparietal cystectomy in four cases, an ovariectomy in seven cases, and the simple removal of the cyst in one case where self-amputation had occurred. In two cases of bilateral pathology, the cysts, which were <1 cm, were left untreated. RESULTS: Average operating time was 40 min (range, 25-60 min). Intraabdominal pressure never exceeded 6-8 mmHg during the intervention. The postoperative course was always under 3 days. No intra- or postsurgical complications were recorded, and long-term ultrasonographic follow-ups were all normal. CONCLUSION: Our experience indicates that the laparoscopic approach is a reliable and safe technique in the treatment of neonatal ovarian cysts.

Female↗
PubMed1998

Splenectomy in childhood. The laparoscopic approach.

BACKGROUND: We set out to analyze the results of the first 19 laparoscopic splenectomies performed by our team in order to show the advantages and limitations of the laparoscopic approach to this kind of procedure in children. METHODS: Between March 1994 and June 1997, 19 children underwent laparoscopic splenectomy; two of them also had a concomitant cholecystectomy. Their ages ranged between 4 and 14 years (median, 7.2 years). There were 14 girls and 5 boys. All the patients underwent elective laparoscopic splenectomy: seven children had hereditary spherocytosis, six were affected by a beta thalassemia, five had an idiopathic thrombocytopenia purpura, and one presented with sickle cell disease. RESULTS: Mean operating time was 145 min (range, 110-240 min). Hospital stay ranged from 2 to 5 days (median, 3 days). In three patients, the spleen was removed with a 7-cm mini-laparotomy, according to the technique of Pfannenstiell, in the suprapubic region. In the other 16 cases, the spleen was captured into a extraction bag, finger-fragmented, and removed from the umbilical orifice. CONCLUSIONS: Laparoscopic splenectomy can be performed only when the spleen can be removed through the umbilical orifice with an extraction bag. For this reason, preoperative ultrasonography is necessary to measure the exact spleen volume. When the spleen is very large, an open splenectomy is preferable.

Adolescent↗
PubMed1998

Transglutaminase-synthesized gamma-(glutamyl5) spermidine derivative of substance P is a selective tool for neurokinin-2 receptors characterization.

The ability of transglutaminase-synthesized 1,3-diaminopropane, spermidine (Spd), spermine (Spm), and monodansylcadaverine gamma-(glutamyl5)derivatives of substance P (SP) to produce bronchoconstriction was investigated. In urethane-anaesthetized guinea pigs, intravenous injections of SP derivatives contracted differently bronchial smooth muscle and caused hypotension. The most effective bronchoconstrictor among SP analogs was the gamma-(glutamyl5)Spd derivative of SP (Spd-SP; EC50 = 5.3 nmol/kg), which was more potent than the native peptide (EC50 = 26.5 nmol/kg). In contrast, the gamma-(glutamyl5)Spm derivative of SP (Spm-SP) was found completely unable to cause bronchoconstriction and was significantly less effective than SP in determining hypotension. The contractile effect of Spd-SP and Spm-SP was investigated in vitro on rat isolated colon, a well-characterized preparation rich in NK2 receptors. In addition, Spd-SP was tested on the endothelium-denuded rabbit pulmonary artery (RPA) and the hamster isolated trachea (HT), both tissue preparations containing only a single functional receptor subtype (NK2A and NK2B, respectively). The results obtained showed that Spd-SP recognizes NK2 receptors occurring on rat isolated colon more effectively (EC50 = 11 nM) than the native peptide (EC50 = 45 nM). Conversely, Spm-SP evokes a contractile response less effective than that elicited by SP (EC50 = 312 nM). Furthermore, Spd-SP (0.1-10 microg kg(-1)) produced a concentration-dependent contraction of both HT and RPA, exhibiting a potency respectively 12 and 30 times higher than SP in contracting HT and RPA. Our results indicate that the introduction of a Spd moiety at the level of glutamine-5 of SP gives rise to an analog that possesses a different capability to recognize NK2 receptors than the parent peptide. Moreover, since Spd-SP seems to contract more effectively RPA than HT, we conclude that it preferentially recognizes the NK2A receptor subtype.

Animals↗
PubMed1998

Strain differences rather than hyperglycemia determine the severity of glomerulosclerosis in mice.

BACKGROUND: We reported that ROP, but not C57, mice were prone to glomerulosclerosis (GS) after nephron reduction (J Clin Invest 97:1242, 1996). METHODS: In this study, we induced diabetes in ROP and C57 mice to determine if the glomerulosclerotic response was stimulus specific. We used the oligosyndactyly mutation (Os), to produce a congenital 50% reduction in nephron number. Stable hyperglycemia was induced by streptozotocin and mice were maintained for 12 weeks without insulin treatment. RESULTS: Glomerular hypertrophy occurred in diabetic ROP +/+ and C57 +/+ mice, but glomeruli of diabetic ROP +/+ mice had 1.92-fold higher laminin B1 and 1.5-fold higher tenascin mRNA levels than diabetic C57 +/+ mice. Diabetic ROP Os/+ mice had severe glomerulosclerosis with arteriolar and tubulointerstitial lesions while there was only moderate mesangial sclerosis in diabetic C57 Os/+ mice. Glomerular size was increased in all non-diabetic Os/+ mice. It was further increased in diabetic ROP Os/+ mice, but not in diabetic C57 Os/+ mice. Glomerular mRNA levels were higher in diabetic ROP OS/+ than in diabetic C57 OS/+ mice [alpha 1 (i.v.) collagen 3.2-fold, laminin B1 2.1-fold, and tenascin 1.6-fold]. CONCLUSION: Overall, our data further support the hypothesis that the susceptibility to glomerulosclerosis is inherited, and suggest that hyperglycemia serves principally as a triggering event in the development of diabetic nephropathy. Since the acceleration of diabetic nephropathy by nephron reduction was also largely strain dependent, it appears that the propensity to glomerulosclerosis is a general renal response and is not stimulus specific.

Animals↗
PubMed1998

Stimulation of hepatocyte growth factor in human acute renal failure.

Hepatocyte growth factor (HGF) is a potent mitogen for tubular cells. Experimental injury to the kidney is associated with HGF release both locally and by distant organs stimulated by circulating 'injurins'. In this study, the serum HGF concentration was measured in patients with acute renal failure (ARF). Normal subjects and chronic renal failure patients either not on dialysis or on regular dialysis treatment served as controls. Human mesangial cells were incubated with sera from ARF patients and controls. The serum HGF concentration was strikingly increased in ARF patients (478 +/- 68 ng/dl) and was normal in chronic renal failure patients not on dialysis (20 +/- 3 ng/dl) and in those on regular dialysis treatment (25 +/- 3 ng/dl). Serum of ARF patients strongly stimulated HGF release from mesangial cells (1,384 +/- 55 ng/ml) in comparison with normal serum (67 +/- 10 ng/ml). These results indicate that in ARF HGF participates in tubular repair both as an endocrine factor, released in the circulation, and as a paracrine substance, diffusing to the tubules from the mesangium.

Acute Kidney Injury↗