Anatomic characteristics of foramen vesalius

OBJECTIVES

Foramen Vesalius is an inconstant foramen that gives passage to an emissary vein that connects pterygoid venous plexus with cavernous sinus, the importance of which lies in the fact that an infected thrombus from an extracranial source may reach cavernous sinus. This study presents some data on characteristics of foramen vesalius.

METHODS

We studied 70 sides of 35 dried adult human skulls available in the Department of Anatomy, Manipal College of Medical Sciences, Pokhara, Nepal. Variation in number and incidence of foramen Vesalius were noted. Differences between the right and the left side and between the male and the female sex are discussed.

MAIN FINDINGS

Foramen Vesalius was present in 23 sides (14 right, 9 left) out of the 70 sides observed, the incidence being 32.85% (20.0% right side, 12.85% left side) of all the sides observed. Incidence of bilateral and unilateral foramen vesalius was 22.85% (8 out of 35 skulls) and 20% (7 out of 35 skulls) respectively. Foramen vesalius was found in 10 sides in males and in 13 sides in females. No remarkable differences were observed in the incidence of foramen vesalius between the sides within same sex but the incidence was more in females compared to male skulls. SIGNIFICANCE OF FINDINGS: Anatomic variations of the foramen vesalius could be explained by developmental reasons. Knowledge about characteristics of foramen vesalius and its incidence is not only important for anatomists but equally essential for an operating surgeon.

Anatomic variations of foramen ovale

OBJECTIVES

Foramen ovale is of great surgical and diagnostic importance in procedures like percutaneous trigeminal rhizotomy for trigeminal neuralgia, transfacial fine needle aspiration technique in perineural spread of tumour and electroencephalographic analysis for seizure. This study presents the anatomic variations in dimensions, appearance and number of foramen ovale.

METHODS

We studied 35 dried human skulls available in the Department of Anatomy, Manipal college of Medical Sciences, Pokhara, Nepal. Variations in appearance and number of foramen ovale were noted. Length and width of foramen ovale was measured. Comparison with other races and differences between right and left sides were also discussed.

RESULTS

Out of 70 sides in 35 adult skulls, mean length and width of foramen ovale was 7.46+/-1.41 mm and 3.21+/-1.02 mm on right side and 7.01+/-1.41 mm and 3.29+/-0.85 mm on left side. Shape of foramen ovale was typically oval in 43, (22 on right, 21 on left) almond shape in 24 (Fig.1, arrowhead; 11 right, 13 left), round in 2(1 right, 1 left) and slit-like in 1(Fig.1, arrow). Bilateral oval foramen was observed in 15 and bilateral almond was in 7. Out of 70 sides in 35 adult skulls 3 (2 left, 1 right) sides had spine on the margin of the foramen (Fig.2, arrow), 3 (2 left, 1 right) had tubercle protruding from the margin (Fig. 3, arrow), 2 (1 left, 1 right) sides had bridge like bony spur dividing the foramen into two compartments(Fig. 2, arrowhead), 9 (5 left, 4 right) had bony plate on the margin of foramen ovale (Fig. 4, arrow). Variant foramen ovale was observed in 24.2%.

CONCLUSION

Anatomical variations in size and shape of foramen ovale could be explained by developmental reasons. Considering the immense surgical and diagnostic importance of foramen ovale, this study was worthwhile.

Gene organization and sequences of pediocin AcH/PA-1 production operons in Pediococcus and Lactobacillus plasmids

AIMS

To determine the locations and sequences of pediocin AcH production genes in Pediococcus parvulus ATO77 from vegetables, Lactobacillus plantarum WHE92 from Muenster cheese, and a lactose-fermenting isolate Pediococcus pentosaceus S34 from buffalo milk.

METHODS AND RESULTS

Plasmid curing, Southern blot hybridization, and DNA sequence analysis indicate that pediocin AcH production genes are encoded by highly similar operons in unique plasmids designated pATO77 from P. parvulus ATO77, pS34 from P. pentosaceus S34, and pWHE92 from Lact. plantarum WHE92. Structure, immunity and secretion system genes are linked together in the operons, and the promoter sequences are the same. The amino acid sequences of the encoded proteins are highly conserved between plasmids.

CONCLUSIONS

Pediocin AcH production genes are located within a plasmid-borne operon cassette in all lactic acid bacterial strains examined to date. All four genes needed for production are present within a single plasmid in each strain.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first demonstration that the expression of a class IIa bacteriocin is directed by a common gene cassette that has been disseminated to unique plasmids in different genera of lactic acid bacteria. These plasmids should be useful for expressing pediocin AcH in Pediococcus and Lactobacillus strains used in food production.

Large loop excision and cold coagulation for management of cervical intraepithelial neoplasia

OBJECTIVES

To evaluate the efficacy of large loop excision of the transformation zone (LLETZ) combined with a single application of the cone probe of a Semm Cold Coagulator as a new treatment for women with cervical intraepithelial neoplasia (CIN).

METHODS

Retrospective case-record review of 666 women treated with large loop excision and cold coagulation (LLECC) from 1992 to 2000.

RESULTS

Of the women who had high-grade CIN at their initial consultation, 4.2% had abnormal cytologic results 6 months after treatment and 0.6% had abnormal cytologic results at 12 months. Of the women who had low-grade CIN at initial presentation, 3.8% had abnormal cytologic results 6 months after treatment and none (0%) at 12 months. Furthermore, there were no reported cases of cervical cancer in this cohort of women during the follow-up period. Short-term bleeding complications (within 24 h of the procedure) occurred in 1% of the women assessed.

CONCLUSIONS

Large loop excision combined with cold coagulation is a new and effective treatment for CIN. Randomized controlled trials are required to confirm these findings and determine the long-term safety of the technique.

A comparative study of aortic wall stress using finite element analysis for ruptured and non-ruptured abdominal aortic aneurysms

BACKGROUND

The decision to repair an asymptomatic abdominal aortic aneurysm (AAA) is currently based on diameter (> or =5.5 cm) alone. However, aneurysms less than 5.5 cm do rupture while some reach greater than 5.5 cm without rupturing. Hence the need to predict the risk of rupture on an individual patient basis is important. This study aims to calculate and compare wall stress in ruptured and non-ruptured AAA.

METHODS

The 3D geometries of AAA were derived from CT scans of 27 patients (12 ruptured and 15 non-ruptured). AAA geometry, systolic blood pressure and literature derived material properties, were utilised to calculate wall stress for individual AAA using finite element analysis.

RESULTS

Peak wall stress was significantly higher in the ruptured AAA (mean 1.02 MPa) than the non-ruptured AAA (mean 0.62 MPa). In patients with an identifiable site of rupture on CT scan, the area of peak wall stress correlated with rupture site.

CONCLUSIONS

Peak wall stress can be calculated from routinely performed CT scans and may be a better predictor of risk of rupture than AAA diameter on an individual patient basis.

Sex-steroid derived compounds induce sex-specific effects on autonomic nervous system function in humans

The physiological and psychological effects of 2 human sex-steroid derived compounds, 4.16-androstadien-3-one (AND) and l,3,5(10),16-estratetraen-3-ol(EST) were measured in 24 subjects who participated in a within-subjects, double-blind experiment. A dissociation was evident in the physiological effects of AND, in that it increased physiological arousal in women but decreased it in men. EST did not significantly affect physiological arousal in women or men. Neither compound significantly affected mood. AND is an androgen derivative that is the most prevalent androstene in human male sweat, male axillary hair, and on the male axillary skin surface. The authors argue that AND's opposite effects on physiology in men and women further implicate this compound in chemical communication between humans.

Viability loss and morphology change of foodborne pathogens following exposure to hydrostatic pressures in the presence and absence of bacteriocins

Cell suspensions of three pathogens were exposed to hydrostatic pressure (HP), bacteriocin mixture (nisin and pediocin) or a combination of HP+bacteriocins and changes in colony forming units (cfu) and cell-morphology by scanning electron microscopy (SEM) were studied. Cell viability loss, as determined from the reduction in cfu before and after a treatment, occurred in Listeria monocytogenes by all three treatments and in Salmonella typhimurium and Escherichia coli O157:H7 by HP and HP+bacteriocin combination. Cell wall and cell membrane collapse and cell lysis was indicated in L. monocytogenes exposed to bacteriocin or HP+bacteriocin and in Salmonella and E. coli exposed to HP or HP+bacteriocin.

Effect of polymer tacticity on the molecular structure of polyelectrolyte/surfactant stoichiometric complexes in solutions and gels

The molecular structure of polystyrene sulphonate/CTAB stoichiometric complexes has been examined by means of small-angle neutron scattering in solutions and in the gel state for two different tacticities of the polystyrene moiety, namely atactic polystyrene and isotactic polystyrene. It is found that tacticity has no influence on the molecular structure in solution, while it plays a role in the gel state. The neutron scattering curves are interpreted with different helical models. The thermal properties of the gels are discussed in the light of the neutron scattering outcomes.

Carcinoma in the gastric pouch years after vertical banded gastroplasty

A 67-year-old lady presented with anemia and weight loss 15 years after vertical banded gastroplasty. The cancer was confined to the pouch, which is suggestive of a relationship to the anti-obesity surgery. A brief review with possible contributing factors is presented.

Conformational changes in pediocin AcH upon vesicle binding and approximation of the membrane-bound structure in detergent micelles

Pediocin AcH is a 44-residue antimicrobial peptide with bactericidal potency against Gram-positive bacteria such as Listeria. It belongs to a family of bacteriocins that, when membrane-associated, is predicted to contain beta-sheet and alpha-helical regions. All bacteriocins in this family have a conserved N-terminal disulfide bond. An additional C-terminal disulfide bond in pediocin AcH is thought to confer enhanced potency and broader specificity range against sensitive bacteria. The C-terminal disulfide bond may also affect the conformation of the C-terminus. The secondary structures of pediocin AcH in aqueous solution and vesicles from susceptible cells, as well as the ability of trifluoroethanol (TFE) and detergent systems to induce secondary structures like those induced in vesicles, were studied by circular dichroism (CD) spectroscopy. Like related peptides, pediocin AcH was highly unordered in aqueous solution, 56%. However, it also contained 20% beta-strand and 15% beta-turn structures. Upon complete binding to vesicles, 32% alpha-helical structure formed, the unordered structure decreased to 32%, and the beta-strand and beta-turn structures remained largely unchanged. Thus, a betaalpha domain structure formed in vesicles. The helical structure likely forces the C-terminal tail to loop back on the helix so that the C24-C44 disulfide bond can form. Detergent micelles were superior to TFE in their ability to induce secondary structural fractions in pediocin AcH comparable to those observed in vesicles. This demonstrates the importance of a hydrocarbon-water interface to pediocin AcH structure induction and suggests that it is preferable to use detergent micelles as solvents in NMR studies of pediocin AcH structure.

Structural features of a water soluble gum polysaccharide from Murraya paniculata fruits

A water soluble gum polysaccharide was isolated from Murraya paniculata fruits. Hydrolytic experiments, methylation analysis, periodate oxidation studies and NMR data revealed that the polysaccharide was extensively branched and it consisted of 1,3-, and 1,3,6-linked beta-D-galactopyranosyl units, terminal beta-D-galactopyranosyl units and terminal alpha-D-glucopyranosyl 1,4-beta-D-galactopyranosyl units. Small amounts of 4-O-methylglucuronic acid residues were also present.

Role of the medial preoptic area in thermal preference of rats

This study was conducted to find out whether the medial preoptic area (mPOA) plays a role in the selection of ambient temperature by rats. Adult male Wistar rats were kept in an environmental chamber having three interconnected compartments, maintained at three different temperatures (18 degrees, 24 degrees and 30 degrees C) in which the animals could move freely from one compartment to the other. Normal rats preferred to stay at the chamber maintained at 24 degrees C for most of the time, during day and night. The temperature preference shifted to 30 degrees C after the mPOA of these rats had been lesioned by local administration of 5 micrograms of N-methyl D-aspartic acid (NMDA) in 0.2 microliter distilled water. The results of the study suggest that the mPOA acts as a fine tuning center for homeostatic regulation of thermal balance, including selection of appropriate thermal environment. It is proposed that after the mPOA lesion, the animal cannot assess properly the energy status of the body and thereby prefers a higher ambient temperature.

Molecular typing of HLA-A, -B, and DRB using a high throughput micro array format

The goal of this study was to develop a DNA micro array procedure for molecular human leukocyte antigen (HLA) typing of a large number of samples. DNA was isolated from peripheral blood samples and polymerase chain reaction (PCR) amplified for HLA-A, -B, and -DRB. Amplified DNA samples were spotted on silane-treated glass slides using a micro array spotter. The spotter was capable of spotting multiple slides with up to 9216 samples per slide or 2304 samples in quadruplicate. The allele specific oligo nucleotide probes for HLA-A, -B, and -DRB were labeled with the fluorescent dye Cy3, while a control probe, to quantitate the total amount of PCR product in a sample, was labeled with Cy5. Each slide was hybridized with a mixture of an allele specific Cy3 probe plus the control Cy5 probe. Following hybridization and wash, the amount of probe hybridizing to each DNA sample on the slide was measured with a micro array scanner. A computer program was used for image analysis, to calculate the average Cy3/Cy5 ratios and to identify the positive and negative samples. In turn, this information was used to determine the HLA phenotype of each sample. There was very good concordance between the results obtained for all three loci using Cy-labeled probes as compared with those previously obtained by chemiluminescent detection of alkaline phosphatase labeled probes. This methodology has the potential of greatly simplifying HLA molecular typing of large number of samples.

Isolation, purification and some structural features of the mucilaginous exudate from Musa paradisiaca

The water-soluble polysaccharides isolated from the vascular gel of Musa paradisiaca, were fractionated via anion exchange chromatography into four fractions. Fractionated polymers contained arabinose, xylose and galacturonic acid as major sugars, together with traces of galactose, rhamnose, mannose and glucose residues. Methylation analysis revealed the presence of a highly branched arabinoxylan with a significant amount of terminal arabinopyranosyl units and an arabinogalactan type I pectin. Periodate oxidation studies supported the results of methylation analysis.

Emergence of a new Vibrio parahaemolyticus serotype in raw oysters: A prevention quandary

CONTEXT

In May and June 1998, reported Vibrio parahaemolyticus infections increased sharply in Texas.

OBJECTIVE

To determine factors that contributed to the increase in V parahaemolyticus infections.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional survey of persons reporting gastroenteritis after eating seafood in Texas; survey of environmental conditions in Galveston Bay.

MAIN OUTCOME MEASURES

Traceback of oysters, water quality measures in harvest areas, presence of V parahaemolyticus in stool cultures; comparison of median values for environmental conditions before and during the outbreak compared with during the previous 5 years.

RESULTS

Between May 31 and July 10, 1998, 416 persons in 13 states reported having gastroenteritis after eating oysters harvested from Galveston Bay. All 28 available stool specimens from affected persons yielded V parahaemolyticus serotype O3:K6 isolates. Oyster beds met current bacteriologic standards during harvest and fecal coliform counts in water samples were within acceptable limits. Median water temperature and salinity during May and June 1998 were 30.0 degrees C and 29.6 parts per thousand (ppt) compared with 28.9 degrees C and 15.6 ppt for the previous 5 years (P<.001).

CONCLUSIONS

This is the first reported outbreak of V parahaemolyticus serotype O3:K6 infection in the United States. The emergence of a virulent serotype and elevated seawater temperatures and salinity levels may have contributed to this large multistate outbreak of V parahaemolyticus. Bacteriologic monitoring at harvest sites did not prevent this outbreak, suggesting that current policy and regulations regarding the safety of raw oysters require reevaluation. Consumers and physicians should understand that raw or undercooked oysters can cause illness even if harvested from monitored beds. In patients who develop acute gastroenteritis within 4 days of consuming raw or undercooked oysters, a stool specimen should be tested for Vibrio species using specific media. JAMA. 2000;284:1541-1545.

Interactions of high hydrostatic pressure, pressurization temperature and pH on death and injury of pressure-resistant and pressure-sensitive strains of foodborne pathogens

The objective of this study is to determine the interactions between high hydrostatic pressure, pressurization temperature, time and pH during pressurization on death and injury of pressure-resistant and pressure-sensitive strains of four foodborne pathogens: Staphylococcus aureus 485 and 765, Listeria ,monocytogenes CA and OH2, Escherichia coli O157:H7 933 and 931, Salmonella enteritidis FDA and Salmonella typhimurium E21274. Among these strains S. aureus 485, L. monocytogenes CA, E. coli O157:H7 933 and S. enteritidis FDA were reported to be more pressure-resistant than the respective strain of the same species (Alpas et al., 1999). In general, viability loss of all pathogens was enhanced significantly as the level of pressure and temperature were increased (P < 0.05). All the strains except S. aureus 485 demonstrated more than 8 log cycle reduction when pressurized at 345 MPa at 50 degrees C for 5 min. This strain seemed to be the most pressure-resistant strain within the conditions of the study. Pressurization in the presence of either citric or lactic acid increased the viability loss by an additional 1.2-3.9 log cycles at pH 4.5 for both acids at 345 MPa. This study has indicated that high hydrostatic pressure applied in conjunction with mild heat and acidity can be an effective method for inactivating pressure-resistant and pressure-sensitive strains of four foodborne pathogens in organic acid solutions. This combination treatment indicates possible pressure pasteurization applications to liquid foods that have low pH. reserved.

A survey of stool culturing practices for vibrio species at clinical laboratories in Gulf Coast states

Non-cholera Vibrio infections are an important public health problem. Non-cholera Vibrio species usually cause sporadic infections, often in coastal states, and have also caused several recent nationwide outbreaks of gastroenteritis in the United States. We report a survey of laboratory stool culturing practices for Vibrio among randomly selected clinical laboratories in Gulf Coast states (Alabama, Florida, Louisiana, Mississippi, and Texas). Interviews conducted with the microbiology supervisors of 201 clinical laboratories found that 164 (82%) received stool specimens for culture. Of these, 102 (62%) of 164 processed stool specimens on site, and 20 (20%) of these 102 laboratories cultured all stool specimens for Vibrio, indicating that at least 34,463 (22%) of 152, 797 stool specimens were cultured for Vibrio. This survey suggests that despite an increased incidence of non-cholera Vibrio infections in Gulf Coast states, a low percentage of clinical laboratories routinely screen all stool specimens, and fewer than 25% of stool specimens collected are routinely screened for non-cholera Vibrio.

Vibrio parahaemolyticus infections in the United States, 1973-1998

Vibrio parahaemolyticus infections are associated with consumption of raw or undercooked shellfish, contaminated food, and exposure of wounds to warm seawater. Foodborne outbreaks and sporadic infections from Vibrio species in 4 Gulf Coast states are reported routinely to the Centers for Disease Control and Prevention (CDC). Between 1988 and 1997, 345 sporadic V. parahaemolyticus infections were reported: 59% were gastroenteritis, 34% were wound infections, 5% were septicemia, and 2% were from other exposures. Forty-five percent of patients suffering from these conditions were hospitalized for their infections, and 88% of persons with acute gastroenteritis reported having eaten raw oysters during the week before their illness occurred. Between 1973 and 1998, 40 outbreaks of V. parahaemolyticus infections were reported to the CDC, and these outbreaks included >1000 illnesses. Most of these outbreaks occurred during the warmer months and were attributed to seafood, particularly shellfish. The median attack rate among persons who consumed the implicated seafood was 56%. To prevent V. parahaemolyticus infections, persons should avoid consumption of raw or undercooked shellfish and exposure of wounds to seawater.

Consequences of placing an intramolecular crosslink in myosin S1

This paper describes the placement of a crosslinking agent (dibromobimane) between two thiols (Cys-522 and Cys-707) of a fragment, "S1," of the motor protein, myosin. It turns out that fastening the first anchor of the crosslinker is easy and rapid, but fastening the second anchor (Cys-522) is very temperature dependent, taking 30 min at room temperature but about a week on ice. Moreover, crystallography taken at 4 degrees C would seem to predict that the linkage is impossible, because the span of the crosslinking agent is much less than the interthiol distance. The simplest resolution of this seeming paradox is that structural fluctuations of the protein render the linkage increasingly likely as the temperature increases. Also, measurements of the affinity of MgADP for the protein, as well as the magnetic resonance of the P-atoms of the ADP once emplaced, suggest that binding the first reagent anchor to Cys-707 initiates an influence that travels to the rather distant ADP-binding site, and it is speculated what this "path of influence" might be.

Variation in resistance to hydrostatic pressure among strains of food-borne pathogens

Among food-borne pathogens, some strains could be resistant to hydrostatic pressure treatment. This information is necessary to establish processing parameters to ensure safety of pressure-pasteurized foods (N. Kalchayanand, A. Sikes, C. P. Dunne, and B. Ray, J. Food Prot. 61:425-431, 1998). We studied variation in pressure resistance among strains of Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella species at two temperatures of pressurization. Early-stationary-phase cells in 1% peptone solution were pressurized at 345 MPa either for 5 min at 25 degrees C or for 5, 10, or 15 min at 50 degrees C. The viability loss (in log cycles) following pressurization at 25 degrees C ranged from 0.9 to 3.5 among nine L. monocytogenes strains, 0.7 to 7.8 among seven S. aureus strains, 2.8 to 5.6 among six E. coli O157:H7 strains, and 5.5 to 8.3 among six Salmonella strains. The results show that at 25 degrees C some strains of each species are more resistant to pressure than the others. However, when one resistant and one sensitive strain from each species were pressurized at 345 MPa and 50 degrees C, the population of all except the resistant S. aureus strain was reduced by more than 8 log cycles within 5 min. Viability loss of the resistant S. aureus strain was 6.3 log cycles even after 15 min of pressurization. This shows that strains of food-borne pathogens differ in resistance to hydrostatic pressure (345 MPa) at 25 degrees C, but this difference is greatly reduced at 50 degrees C. Pressurization at 50 degrees C, in place of 25 degrees C, will ensure greater safety of foods.

The pediocin AcH precursor is biologically active

The properties of the pediocin AcH precursor, prepediocin AcH, have been studied to gain insight into how producer cells may protect themselves from the activity of intracellular prebacteriocins. The native 62-amino-acid precursor and the 44-amino-acid mature species were expressed in Escherichia coli host strains that lack the leader peptide processing enzyme, PapD. Both forms inhibited the growth of the test bacterium Listeria innocua Lin11, indicating that the native precursor is biologically active. The two species also were synthesized in the context of maltose-binding protein chimeric proteins to facilitate the measurement of their relative specific activities. The chimeric form of the precursor was approximately 80% as active as the chimeric mature species. Of relevance to cell protection and pediocin AcH production, it was determined that the precursor is strongly susceptible to inactivation by reducing agents and to degradation by chymotrypsin and endogenous E. coli proteases. Taken together, the results indicate that the activity of prepediocin AcH may have to be controlled prior to secretion to prevent toxicity to the host. Perhaps producer cells avoid membrane damage by maintaining the precursor in a reduced inactive state or by degrading molecules whose secretion is delayed.