Cerebrospinal Fluid Density Influences Extent of Plain Bupivacaine Spinal Anesthesia

Background: The attempts to explain the unpredictability of extent of spinal block provided by plain local anesthetic solutions have resulted in many clinical reports; however, causes of this uncertainty are as yet unknown. Recently, normal values of the human cerebrospinal fluid densities have been studied showing important interindividual variations, especially between females and males. The current study was designed to evaluate as primary endpoint the influence of cerebrospinal fluid density values on the extent of spinal block with plain bupivacaine. The ancillary endpoints were search of factors explaining the interindividual differences in cerebrospinal fluid density values reported and determination of the relation between upper extent and regression of spinal anesthesia.

Methods: Sixty-four consecutive patients undergoing peripheral orthopedic surgery with spinal block were enrolled. Spinal anesthesia was performed in the lateral decubitus position with the operated side upward. Two milliliters of cerebrospinal fluid was sampled before injection of 3 ml plain bupivacaine 0.5%. The patient was immediately turned supine and remained in the horizontal position until the end of the study. Maximal sensory block level and time to sensory regression to L4 were determined for each patient enrolled. Cerebrospinal fluid and bupivacaine densities as well as cerebrospinal proteins, glucose, sodium, and chloride concentrations were measured.

Results: A highly significant correlation between cerebrospinal fluid density and maximal sensory block level was found (P = 0.0004). However, this correlation was poorly predictive (R2 = 0.37). Cerebrospinal fluid density, proteins, and glucose concentrations were significantly higher in men than in women: 1.000567 +/- 0.000091 versus 1.000501 +/- 0.000109 g/ml (P = 0.014), 0.46 +/- 0.18 versus 0.32 +/- 0.13 g/l (P = 0.001), and 3.27 +/- 0.7 versus 2.93 +/- 0.5 mm (P = 0.023), respectively. A highly significant (P = 0.0004) and predictive (R2 = 0.73) inverse correlation was found between maximal upper sensory extent and sensory regression to L4.     

Ovarian and uterine findings in pelvic sonography: comparison between prepubertal girls, girls with isolated thelarche, and girls with central precocious puberty.

OBJECTIVE: To describe pelvic sonographic findings in girls as old as 7 years, to compare prepubertal girls with girls who had isolated thelarche or central precocious puberty, and to verify the accuracy of sonographic variables for distinguishing prepubertal girls from girls with central precocious puberty. METHODS: Ninety-six prepubertal girls and 2 reference groups (8 girls with isolated thelarche and 8 with idiopathic central precocious puberty) were included. Ovaries were classified morphologically as homogeneous, paucicystic, macrocystic, multicystic, and having isolated cysts. Receiver operating characteristic curves were used to choose the best cutoff points. RESULTS: Chronologic and bone age were correlated with uterine length, area, and volume and ovarian volume in prepubertal girls (P < .0001). Ovarian morphologic characteristics in prepubertal girls differed significantly from those of the reference groups (P < .0001). The best cutoff points were uterine length of 4.0 cm, uterine area of 4.5 cm2, uterine volume of 3.0 cm3, and ovarian volume of 1.0 cm3. CONCLUSIONS: Uterine and ovarian growth are proportional to age in prepubertal girls. Mean ovarian volume greater than 1 cm3 showed 100% sensitivity and specificity for discriminating between prepubertal girls and girls with central precocious puberty. Microcysts are common in prepubertal girls, but the presence of 6 or more follicles up to 10 mm in diameter may suggest central precocious puberty in girls younger than 8 years.     

Endothelial Vascular Function in Hypertensive Patients After Renin—Angiotensin System Blockad

It is unclear whether single and combined pharmacologic inhibition of the renin-angiotensin-aldosterone system have similar effects on endothelial function and blood pressure (BP). The authors evaluated 63 hypertensive patients divided into 4 groups (hydrochlorothiazide 25 mg/d; irbesartan [IRBE] 150 mg/d; quinapril [QUIN] 20 mg/d; or IRBE 150 mg/d + QUIN 20 mg/d) and 25 healthy normotensive subjects (normal) followed for 12 weeks. Endothelium-dependent dysfunction measured as flow-mediated dilation at Weeks 0 and 12 were: normal, 11.5%±2.4% vs 13.5%±2.0%; hydrochlorothiazide, 7.3%±2.0% vs 12.8%±3.1%; QUIN, 7.2%±2.8% vs 13.2%±2.1%; IRBE, 7.1%±2.8% vs 13.0%±2.9%; and IRBE + QUIN, 7.5%±1.9% vs 12.8%±3.0%. Nitroglycerin-mediated responses were: normal, 26.0%±1.9% vs 24.0%±2.5%; hydrochlorothiazide, 17.0%±2.2% vs 18.3%±2.6%; QUIN, 17.8%±3.2% vs 23.4%±3.0%; IRBE, 16.8%±3.6% vs 24.7%±2.0%; and IRBE + QUIN, 17.3%±3.0% vs 25.1%±2.5%. Antihypertensive therapy restored BP to normal and improved the endothelium-dependent and -independent dysfunction after renin-angiotensin-aldosterone system blockade. In a further finding, the combined effect of angiotensin-converting enzyme inhibition and angiotensin II type 1 receptor blockade was not superior to the action of either of these treatments separately.     

Linitis plástica primaria rectal

Primary linitis plastica of the rectum is an infrequent and unusual rectal carcinoma. We report a new case that presented clinically as a haemorrhoidal syndrome. We comment on the characteristics--clinical picture and histopathology--of this uncommon presentation of rectal tumour, as well as its clinical history and prognosis taking into account that the literature consulted indicated the unusualness of primary linitis plastica of the rectum.     

An HLA-DRB α-helix motif shared by DR11 and DR8 alleles is implicated in the pluriallelic restriction of peptide-specific T-cell lines

The T-cell recognition of HLA-DR-peptide complexes is generally restricted by the polymorphism of the DRB molecules but pluriallelic restriction has been described. The molecular basis of restriction and promiscuity of such peptide-specific responses is poorly understood. We isolated a panel of T-cell lines specific for the tetanus toxin peptide p2 (TT830-843) exhibiting pluriallelic restriction by DR11 and DR8 alleles. Fine restriction specificity of the T-cell lines was examined in functional assays against DR oligotyped APCs expressing different variants of DR11 and DR8 alleles. Our results show that (a) polymorphisms between serologically related alleles are relevant in terms of restriction of the peptide-specific T-cell response; in some instances, a single amino acid substitution can determine the restriction of a T-cell line; (b) different patterns of restriction are not the result of specific differences in DR-p2 binding as p2 peptide binds to all DR11 and DR8 alleles tested (DRB1^* 1101, -1102, -1103, -1104, 110X, -0801, -0802, -0803, and -0806); and (c) pluriallelic restriction of the peptide-specific T-cell responses correlates with the presence of a DRB1 α-helix motif (67-71-86) shared by some DR11 and DR8 alleles. Possible implications of pluriallelic restriction of peptide-specific T-cell response in autoimmune disorders associated with DR11 and DR8 are discussed.     

Design-based stereological estimation of hepatocyte number, by combining the smooth optical fractionator and immunocytochemistry with anti-carcinoembryonic antigen polyclonal antibodies.

BACKGROUND/AIMS: Hepatocytes (HEP) have been the major target for structural quantification in the liver, but an estimation of their total number (N), their percentage in relation to the global number of liver cells and the evaluation of the percentage of binucleated hepatocytes (BnHEPs) have never been performed with modern design-based stereological techniques. The establishment of sound technical guidelines and baseline quantitative data in non-pathological conditions are relevant to properly evaluate HEP hyperplasia and BnHEP responses. METHODS: In this study, we combined immunocytochemistry with sound design-based stereology for estimating the N of HEP and the N of non-hepatocytic cells (NHCs). For obtaining systematic uniform random sections (30 microm thick), a smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 month old). Those sections were immunostained with polyclonal antibodies against carcinoembryonic antigen. Because biliary canaliculi were then marked, an unequivocal counting of mononucleated hepatocytes (MnHEP) and BnHEP was allowed. RESULTS: The N of HEP was estimated to be 1.93 x 10(9), with a coefficient of error (CE) of 0.02, corresponding to 129 x 10(6) HEP/g of liver. BnHEP represented 26% of total HEP number. The N of NHC was estimated as 1.31 x 10(9) (CE=0.02). CONCLUSION: The strategy here presented provides a reliable method for accessing the N of HEP (distinguishing MnHEP from BnHEP) in situations in which these parameters are relevant, namely for evaluating the magnitude of an hyperplastic liver response from its very early onset.     

Fixation of cementless acetabular cups: A radiographic 4-8-year study of 102 porous-coated components

We studied fixation changes over time in 113 porous-coated Howmedica (PCA) cementless acetabular cups inserted in 90 patients 1984-1988. The mean follow-up was 5 years. Radiographic fixation was classified as stable, fibrous-stable, or unstable. 9 cups, 3 in neutral position and 6 vertical, were revised. At follow-up, 40/75 neutral cups were stable versus 7/27 vertical cups. Most stable cups and two thirds of the unstable cups were clinically good. After the first 2 years, 28/75 neutral cups and 10/27 vertical cups changed their fixation: 12 had improved fixation and 26 had a worse one.     

Rare associations of dens invaginatus and mesiodens.

Dens invaginatus is a developmental variation resulting from an alteration in the normal growth pattern of the dental papilla. Synonyms of this disturbance include dens in dente, invaginated odontome, tooth inclusion, and dentoid in dente. Radiographically, it is observed as infolding of a radiopaque ribbon-like structure, with equal density as enamel, extending from the cingulum into the root canal and sometimes reaching the root apex, assigning the appearance of a small tooth within the coronal pulp cavity. This article presents 2 case reports. The first describes an 8-year-old girl with dens invaginatus in a mesiodens; the second report describes a 16-year-old boy presenting with 2 mesiodens, both associated with dens invaginatus.