Polychromatic staining of epoxy semithin sections: a new and simple method

A simple, rapid method is described for the polychromatic coloration of semithin sections, which is applicable to material routinely processed for transmission electron microscopy. Material fixed with a glutaraldehyde-paraformaldehyde mixture and postfixed in osmium tetroxide with or without potassium ferrocyanide and embedded in different types of resin (Durkupan-ACM, Spurr resin, Taab resin) can be used. Constant and homogenous results are obtained with this technique, the staining procedure being achieved at room temperature in no more than 10 min. Sections of 0.5-1 microns in thickness are oxidised and bleached. After washing, sections are stained in two steps with carbol methylene blue/carbol gentian violet solution and pararosaniline solution. Using the method described in this paper, a polychromatic coloration of the different cells and tissues was obtained (epithelial cells in various shades of blue-violet, connective tissue and elastic laminae of blood vessels in pink or red, etc.). This procedure provides greater contrast between cytoplasm and nuclei, and among the different types of cells and tissues than is seen with toluidine blue, which is very useful for observation and photography of semithin sections. Polychromatic methods found in the literature are normally complex and require a lengthy staining time or cannot be applied on material routinely processed for transmission electron microscopy. Our method is simple, rapid and can be used on any type of material routinely processed for transmission electron microscopy and embedded in epoxy resins.

Subzonal sperm insemination and total or extreme asthenozoospermia: an effective technique for an uncommon cause of male infertility

OBJECTIVE

To assess the value of subzonal insemination (SUZI) in cases of total or extreme asthenozoospermia.

DESIGN

The results of IVF after SUZI were assessed in six cycles (four couples) with documented asthenozoospermia.

SETTING

Institut de Médecine de la Reproduction, Marseille, France.

PATIENTS

Four couples underwent six retrieval cycles. In all cases asthenozoospermia was total (100% of immotile spermatozoa) or extreme (5% nonprogressive motility). Oligozoospermia and teratozoospermia were ruled out in all cases. In two cases electron microscopy revealed the absence of the central singlet in the flagellum axonemal complex and in one case a major dysplasia of the fibrous sheath in the flagellum principal piece.

RESULTS

The overall fertilization rate was 45%. The diploid embryo rate was 33%. Embryo quality was satisfactory. In five of six cycles, three embryos were transferred. Two triplet pregnancies were obtained corresponding to an implantation rate per transferred embryo of 40%.

CONCLUSION

Total or extreme asthenozoospermia seems to be a good indication for SUZI.

[Benign amaurosis fugax]

In young patients episodes of amaurosis fugax usually correspond to processes not related with atherosclerosis of the extracranial vessels such as migraine, cardiac embolism, vasospasm, vasculitis, oral contraceptives or hematologic disease. In 11% of the cases, however, no cause can be found. These idiopathic cases generally have a benign course and their frequency decreases spontaneously allowing them to be described as benign amaurosis fugax. We describe four cases of amaurosis fugax in which no responsible cause was found despite extensive clinical, laboratory ultrasonographic and angiographic studies. The episodes progressively remitted. In these cases of benign amaurosis fugax the risk of a permanent deficit is exceptional and treatment is not necessary.

Rostrocaudal changes in neuronal cell size in human lateral vestibular nucleus

A cytoarchitectonic and morphometric study of the human lateral vestibular nucleus (LVN) is presented. In sagittal sections, the LVN appears as a triangular cell group rostrally located near the motor trigeminal nucleus and caudally near the vestibular root. The estimated volume is 13.49 mm3 with a neuronal population of 25,046 cells and 1855 neurons/mm3 in density. The average neuronal cross-sectional area changes from a minimum caudally (380.02 +/- 7.23 microns 2) to a maximum rostrally (825.16 +/- 25.10 microns 2). Four types of neurons can be observed: small (< 200 microns 2), medium (200-500 microns 2), large (500-100 microns 2) and giant or Deiter's cells (> 1000 microns 2). The small and medium cells constitute 62%, large cells 26% and the giant cells only 12% of the neuronal population.

Morphometric analysis of the vestibular complex in the rat

The characteristics of the four major vestibular nuclei and accessory cell groups in the rat have been studied in serially cut horizontal sections. Camera lucida drawings of the vestibular nuclei and their neurons were made in these sections and subjected to a computerized image analysis. The dimensions (volume and length) and the number of cells of each vestibular nucleus were obtained, as well as morphometric parameters of their neurons (cross-sectional area, maximum and minimum diameter, and shape). These parameters were statistically analyzed by comparing the cell population from different nuclei and different parts of each nucleus. Of the major nuclei, the medial, which is the largest, has the greatest number of cells, its neurons being the smallest of all the nuclei, with the size of cells decreasing in a rostrocaudal direction. In contrast, the lateral nucleus contains the fewest cells but also the largest ones. Neurons of the superior and descending nuclei are of an intermediate size and number, with a rostrocaudal decrease in the size of the descending nucleus cells. In addition, minor nuclei are identified and described in their relationship to the other structures in the brain stem. The relevant aspects of the anatomical information in regard to functional roles are reviewed.

[Intestinal obstruction caused by milk curds in newborns]

Intestinal obstruction due to milk curds syndrome may present with a clinical picture and radiological findings which suggest the correct diagnosis. This type of intestinal obstruction usually affects neonates, previously healthy, with concentrated formula feeding. Surgical treatment may be avoided in some cases by the administration of Gastrografin enemas. Two patients with milk curd obstruction treatment in our Hospital, are presented.

[Food consumption of school children regarding their social condition. Córdoba, Republic of Argentina]

This report reveals the daily consumption of nourishing food in primary school children coming from the north of Córdoba, Argentina, in relationship with their socio economic status, SES. Four categories were determined according to the place the chief support of the family occupies in the productive system. A 24 hours recall test was applied to obtain nutritional data as well as the weight and method of measure. Differences among the established categories were pointed out by socioeconomic indicators (P < 0.001). Powder and liquid milk ingesta showed statistic differences (P < 0.005), at the same time, the consumption of this food was poor, and it was not being incorporated into the scholarship's diet. The per-capita proportion of meat ingesta was over 100 g, in the whole group. Difference (P < 0.005) were noticed among the SES when the consumption was over 200 g. The consumption of fruits and vegetables is low. On the contrary, it was shown an increase in cereals and legumes ingesta as the SES decreased (P < 0.005). Analyzing the fitness of the diet it was found that the 53% of SES IV children showed calorie shortage whereas the proteins evaluation revealed excess consumption in the 88% of the studied scholarships. Other deficiencies were also found, such as calcium, riboflavin, thiamine, niacin in the whole group. This study also showed statistic differences with respect to the consumption of energy, calcium and ascorbic acid (P < 0.05).

Quantified ultrastructural study of spermatozoa in unexplained failure of in vitro fertilization

Failure of in vitro fertilization or very low cleavage rates may occur even though oocyte and semen parameters seem satisfactory. Quantified ultrastructural study of spermatozoa was performed in such cases of failure (n = 6) or low cleavage rate (< 20%; n = 4). Through 1 to 11 retrievals, the number of inseminated oocytes ranged from 14 to 145. The results were compared to those of six fertile men. Quantification was achieved by cataloguing cell defects of the spermatozoon heads and mid-/principal pieces of the flagella. Using the data from each specimen, the percentages of total cellular abnormalities in the head/mid-/principal pieces were established. At the level of the head overall percentages for six groups of defects were determined. The overall percentage of combined head abnormalities, defined as the presence of at least three of these six defects on the same spermatozoon head, was established. Statistical differences among control and patient groups were analyzed by nonparametric Mann-Whitney U test. The percentages of anomalies of the midpiece and of the principal piece were not significantly different between patients and controls. Motility assessed by spermogram was considered "functionally uncompromised." In eight patients the percentage of cell alterations of the head (93-100 vs 77.3 +/- 6.4%) and the percentage of combined anomalies of the head (78.1-100 vs 60.8 +/- 8.5%) were significantly different between patients and controls. In two cases, the percentages established for all head parameters considered were not globally different from those observed in controls. Thus in 8 cases of 10, electron microscopy with quantified analysis supplied valuable evidence about the poor quality of these sperm samples judged as normal under light microscopy and may provide an explanation for their impaired fertilizability.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary structure of an agonist binding subunit of the nicotinic acetylcholine receptor from bovine adrenal chromaffin cells

Activation by acetylcholine of a nicotinic acetylcholine receptor on the membrane of bovine chromaffin cells leads to membrane depolarization and to the subsequent triggering of catecholamine secretion. It is evident that acetylcholine receptors play a central role in the initial phase of the secretion process and, therefore, an extensive characterization of their molecular components and properties is of fundamental interest. With this intention, we have screened bovine adrenal medullary cDNA libraries with a probe coding for a fragment of the rat muscle acetylcholine receptor alpha subunit. Several cDNA clones were isolated. The longest cDNA had an open reading frame encoding a 495-amino acid protein with a molecular weight of 56,911. The deduced primary structure contains features that indicate that the encoded protein is an alpha or acetylcholine binding subunit, and, in fact, it manifests significant sequence similarity to previously cloned alpha subunits. Sequence identity is particularly high with the alpha 3 subunit, which is expressed in the rat pheochromocytoma PC12 cell line and in several brain areas, and, consequently, it is considered a component of a neuronal acetylcholine receptor. Accordingly, the present results suggest that the agonist binding subunit of the nicotinic acetylcholine receptor from bovine chromaffin cells is an alpha 3-type subunit, corroborating previous immunological and pharmacological evidence for the presence of a neuronal nicotinic receptor in chromaffin cells.

Growth in malnutrition related to gastrointestinal diseases: coeliac disease

Coeliac disease in children is frequently associated with a slow growth rate. This observation may be linked to the malabsorption that occurs in these patients; however, the underlying mechanism remains unknown. To better understand this phenomenon, we have studied the growth patterns of 153 patients with coeliac disease for 2-9 years. Gastro-intestinal biopsies were performed before and after gluten exclusion. In a second group of 79 children, somatostatin levels and binding properties in the plasma and jejunal mucosa were measured. In a third group of 40 patients we measured insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGF-BP3) levels. We found that in children diagnosed before 2 years of age weight was the most affected growth parameter. In children diagnosed after this age, height was more affected. Suppression of gluten intake induced an acceleration of growth velocity. Although plasma levels of somatostatin were not significantly altered, somatostatin concentrations in the jejunal mucosa of patients in the active phase of the disease were significantly elevated (p < 0.05). Children with coeliac disease exhibited significantly lower levels of IGF-BP3 when compared to patients with normal stature and growth velocities. In contrast, these patients showed an increase in IGF-BP3 levels after gluten exclusion from the diet.

Two beta-glycanase genes are clustered in Bacillus polymyxa: molecular cloning, expression, and sequence analysis of genes encoding a xylanase and an endo-beta-(1,3)-(1,4)-glucanase

Two genes, xynD and gluB, encoding a xylanase and an endo-beta-(1,3)-(1,4)-glucanase (lichenase) from Bacillus polymyxa have been cloned and expressed in Escherichia coli and Bacillus subtilis. A sequenced DNA fragment of 4,466 bp contains both genes, which are separated by 155 bp. The xynD and gluB genes encode proteins of 67.8 kDa (XYND) and 27 kDa (GLUB). Two peptides with molecular masses of 62 and 53 kDa appear in cell extracts of E. coli and culture supernatants of B. subtilis clones containing the xynD gene. Both peptides show xylanase activity in zymogram analysis. The XYND enzyme also shows alpha-L-arabinofuranosidase activity. The XYND peptide and the xylanase XYNZ from Clostridium thermocellum (O. Grépinet, M. C. Chebrou, and P. Béguin, J. Bacteriol. 170:4582-4588, 1988) show 64% homology in a stretch of about 280 amino acids.

Nucleotide sequence of the cellulase gene celF of Clostridium thermocellum

The nucleotide sequence of the celF gene of Clostridium thermocellum was determined. The open reading frame extended over 2217 bp. The encoded 739-aa polypeptide, CelF, with a Mw = 82,015, was an endoglucanase with activity against carboxymethylcellulose. The N terminus showed a typical signal peptide, and a cleavage site after Ala-27 was predicted. From residues 28 to 470, the sequence of CelF was related to the catalytic domains of type E2 endoglucanases, with a strong homology to the endoglucanases CelZ of Clostridium stercorarium and CenB of Cellulomonas fimi. The catalytic region was followed by a 134-aa segment also present in C. stercorarium CelZ and in C. fimi CenB, and belonging to the family of non-catalytic, presumably cellulose-binding domains first identified in Bacillus subtilis endoglucanase. A 21-aa segment rich in Pro/Thr/Ser residues separated the putative cellulose-binding region from the COOH-terminal region, which contained two conserved stretches of 24 amino acids closely similar to those previously described in endoglucanases CelA, CelB, CelD, CelE, CelH and CelX, and xylanase XynZ of C. thermocellum.

Episodic cluster headache and narcolepsy: a case report

A patient who first presented with episodic cluster headache later developed narcolepsy. In spite of REM sleep alterations associated with narcolepsy, the frequency and distribution of pain attacks did not change when narcolepsy occurred and were similar to those seen in cases of episodic cluster without narcolepsy. The lack of influence of narcolepsy on the pattern of cluster pains questions the role of REM sleep states in triggering pain in episodic cluster.

[Episodic ++paroxysmal hemicrania or chronic paroxysmal hemicrania in pre-chronic state?]

Two women suffered from strictly unilateral, periocular headaches for many years. The clinical characteristics of headaches were those described in chronic paroxysmal hemicrania. However, both patients showed an episodic evolution of pain. In one case, this stage could be considered pre-chronic because it was later followed by the classic and apparently definitive chronic period of the disorder. In the second case the episodic stage persisted all along the evolution of the disease and the headache did not reach the chronic period. The patient has been free of pain without treatment for the last three years. This second observation can be considered as an example of episodic paroxysmal hemicrania. In the episodic cases the response of pain to indomethacin can be difficult to be ascertained.

Interrelationship of capsule thickness and breast hardness confirmed by a new measurement method

All implants initiate a foreign-body response that leads to their encapsulation by scar tissue. In order to better understand this encapsulation process and the differences between soft (comfortable) and firm (contracted) breasts, we studied 22 patients who had come in for reaugmentation during a 2-year period. The capsules removed were prepared and measured using a new method. The capsules were (1) removed and stored in physiologic solution until the time of measurement (30 minutes to 2 hours) and (2) measured using a Mitutoyo dial-thickness gauge (MDTG) that employs a uniform pressure of 85 gm. The measurements revealed that soft breasts (Baker 1) have the thinnest scar-tissue capsules, which ranged in thickness from 0.002 to 0.010 inches. Firm breasts yielded the thickest capsules. Baker 3 measured between 0.010 and 0.078 inches thick, and Baker 4 measured between 0.018 and 0.162 inches thick. We also compared the precision of measurement between the MDTG and a standard (screw-type) micrometer by taking a series of readings on a soft, pliable substance (textured silicone rubber).

[Patterns in the household acceptance of oral rehydration therapy in a cohort of rural mothers]

The household acceptance of oral rehydration solution salts was studied in a cohort of 75 rural mothers over a two year period. The study was carried out in a rural Mexican village between August 1985 and February 1988. There were 636 episodes of diarrhea, with an average of four episodes per child per year. There were no deaths due to diarrhea or its complications and only 2% of these episodes required the use of parenteral solutions. Acceptance of oral rehydration remained around 50% during subsequent bouts of diarrhea. Variables such as a medium high socioeconomic level of the family, and the reading of journals and newspapers by the mother and the presence of water supply in the home were significantly associated with the acceptance of oral rehydration treatment. On the other hand, families classified as traditional rejected the procedure with significantly higher frequency. The data presented indicates the need for redesigning oral rehydration, treatment programs to increase their impact at the community level.

[A comparative study between the use of the Spicer-Edwards method and the coagglutination reaction for identifying Salmonella antigens]

A comparative study between tube agglutination using Spicer-Edwards antisera and a coagglutination method using Staphylococcus aureus Cowan 1 (NCTC 8530) protein A to detect Salmonella flagellar antigens was carried out. A total of 39 Salmonella strains belonging to eight serogroups of the Kauffmann-White scheme were typed by both methods. Each serogroup include monophasic and biphasic strains. Statistical analysis of the results showed that the coagglutination method was more sensitive and specific that the classic tube agglutination method normally used in different laboratories. The use of less antiserum in the coagglutination method to detect Salmonella antigens without loss of specificity or sensitivity represents an important saving for clinical laboratories and for epidemiologic research that require the identification of these antigens.

[The comparative treatment with lovastatin and bezafibrate of primary hypercholesterolemia. A randomized and double-blind trial]

The efficacy and tolerability of lovostatin (L) and bezafibrate (B) were compared in a total of 39 patients, 24 males and 15 females, 59 +/- 9 years old. Showing a total serum cholesterol superior to 250 mg/dl and total serum triglycerides inferior to 350 mg/dl, after 1 month on a low cholesterol diet and another on placebo, were eligible for participation. After randomization 19 treated with L started with 20 or 40 mg at night according to baseline cholesterol under or above 300 respectively and 20 with B received 200 mg tid. If after 6 weeks of therapy cholesterol remained above 200, the doses of L or matching placebo in those with B was double while dose of B or matching placebo remained constant. Cholesterol, triglycerides, LDL-cholesterol and HDL-cholesterol were determined using an enzymatic analytical method. Apolipoproteins were obtained by radial immunodiffusion. Routine hematological analysis and blood chemistry safety tests were performed at baseline and every 6 weeks during active treatment. The average most important results, after 12 weeks of treatment, comparing L vs B were: 1) cholesterol was reduced 26 vs 10% (p less than 0.001); 2) LDL-cholesterol decreased 35 vs 15% (p less than 0.001); 3) HDL-cholesterol increased 5 vs 19% (p = NS); 4) triglycerides diminished 15 vs 18% (p = NS). Three patients in L and 1 in B showed adverse events and two of them, one each group, were drop-out. In summary: a) L was more effective lowering total cholesterol and LDL-cholesterol; b) B was more potent decreasing triglycerides and increasing HDL-cholesterol; c) both drugs showed good tolerability.