Expression profiling in cancer using cDNA microarrays

Currently there are over 1,000,000 human expressed sequence tag (EST) sequences available on the public database, representing perhaps 50-90% of all human genes. The cDNA microarray technique is a recently developed tool that exploits this wealth of information for the analysis of gene expression. In this method, DNA probes representing cDNA clones are arrayed onto a glass slide and interrogated with fluorescently labeled cDNA targets. The power of the technology is the ability to perform a genome-wide expression profile of thousands of genes in one experiment. In our review we describe the principles of the microarray technology as applied to cancer research, summarize the literature on its use so far, and speculate on the future application of this powerful technique.

Prospective randomized trial of bilateral carotid endarterectomies: primary closure versus patching

BACKGROUND AND PURPOSE

Although several studies have compared the results of carotid endarterectomy (CEA) with primary closure (PC) versus patch closure, none have compared the outcome of bilateral CEAs with patch versus PC performed on the same patient. This prospective randomized study compares the clinical outcome and incidence of recurrent stenosis (>/=80%) for CEA with PC versus patch closure in patients with bilateral CEAs.

METHODS

This study includes 74 patients with bilateral CEAs with PC on one side and patching on the other. Patients were randomized to sequential operative treatment of either patching/PC or PC/patching. Postoperative duplex ultrasounds and clinical follow-up were done at 1, 6, and 12 months and every year thereafter. A Kaplan-Meier analysis was used to estimate the risk of significant restenosis (>/=80%).

RESULTS

Demographic characteristics and the mean operative diameter of the internal carotid artery were similar for both PC and patching. The mean follow-up was 29 months (range, 6 to 65 months). The incidence of ipsilateral stroke was 4% for PC versus 0% for patching. PC had a significantly higher incidence of neurological complications (transient ischemic attacks and stroke combined) than patching (12% versus 1%; P=0.02). Operative mortality was 0%. PC had a higher incidence of recurrent stenosis (22% versus 1%; P<0.003) and total internal carotid artery occlusion (8% versus 0%; P=0.04) than patching. Restenoses necessitating a repeated CEA were also higher for PC (14%) than for patching (1%; P=0.01). The Kaplan-Meier analysis showed that patching had a significantly better cumulative patency rate than PC (P<0.01). This analysis also showed that freedom from recurrent stenosis at 24 months was 75% for PC and 98% for patching.

CONCLUSIONS

Patch closure is less likely than PC to cause ipsilateral stroke, transient ischemic attacks, and recurrent carotid stenosis. The higher rate of unilateral recurrent stenosis may suggest that local factors play a more significant role than systemic factors in the etiology of recurrent carotid stenosis.

Nitric oxide synthase inhibitor attenuates intestinal damage induced by zinc deficiency in rats

A nitric oxide synthase (NOS) inhibitor, NG-nitro-L -arginine methyl ester (L-NAME), was given to zinc-deficient (ZD) rats to determine whether it prevents the intestinal damage usually observed under these conditions. Weanling male rats were given free access to a ZD diet (2 mg zinc/kg), whereas control rats including pair-fed (PF) and ad libitum consumption (AL) groups were given a zinc-supplemented (50.8 mg zinc/kg) diet for 4 wk. Half of the ZD rats received L-NAME (0.3 g/L in drinking water) for 3 wk starting at the wk 2 of the deficient period. Plasma zinc concentration in ZD rats was significantly lower (P < 0.05) than that of AL and PF rats. Administration of L-NAME did not alter this concentration. Intestinal zinc concentration did not differ among groups. However, metallothionein-1 (MT-1) mRNA level was significantly lower in the intestine of ZD rats than in AL or PF rats. Treatment of ZD rats with L-NAME did not affect this level. Intestinal microvascular permeability evaluated by Evans blue showed significantly higher extravasation in ZD rats than in AL rats, whereas L-NAME administration inhibited the extravasation. Expression of inducible NOS mRNA was observed in intestine of ZD but not of AL or PF rats, and there was no significant difference between ZD rats, regardless of L-NAME treatment. The activity ratio of inducible NOS to total NOS in ZD rats not receiving L-NAME was significantly higher than that in AL rats or ZD rats treated with L-NAME (P < 0.05). The number of apoptotic-positive and goblet cells in intestinal villi was significantly higher in ZD rats compared with AL or PF rats. L-NAME administration in ZD rats reversed this effect. These results indicate that inhibition of NOS ameliorates zinc deficiency-induced intestinal damage in rats.

DNA microarray technology: the anticipated impact on the study of human disease

One can imagine that, one day, there will be a general requirement that relevant array data be deposited, at the time of publication of manuscripts in which they are described, into a single site made available for the storage and analysis of array data (modeled after the GenBank submission requirements for DNA sequence information). With this system in place, one can anticipate a time when data from thousands of gene expression experiments will be available for meta-analysis, which has the potential to balance out artifacts from many individual studies, thus leading to more robust results and subtle conclusions. This will require that data adhere to some type of uniform structure and format that would ideally be independent of the particular expression technology used to generate it. The pros and cons of various publication modalities for these large electronic data sets have been discussed elsewhere [12], but, practical difficulties aside, general depositing must occur for this technology to reach the broadest range of investigators. Finally, as mentioned at the beginning of this review, it is unfortunate that this important research tool remains largely restricted to a few laboratories that have developed expertise in this area and to a growing number of commercial interests. Ultimately the real value of microarray technology will only be realized when this approach is generally available. It is hoped that issues including platforms, instrumentation, clone availability, and patents [20] will be resolved shortly, making this technology accessible to the broadest range of scientists at the earliest possible moment.

Expression profiling in cancer using cDNA microarrays

Currently there are over 1,000,000 human expressed sequence tag (EST) sequences available on the public database, representing perhaps 50-90% of all human genes. The cDNA microarray technique is a recently developed tool that exploits this wealth of information for the analysis of gene expression. In this method, DNA probes representing cDNA clones are arrayed onto a glass slide and interrogated with fluorescently labeled cDNA targets. The power of the technology is the ability to perform a genome-wide expression profile of thousands of genes in one experiment. In our review we describe the principles of the microarray technology as applied to cancer research, summarize the literature on its use so far, and speculate on the future application of this powerful technique.

Indications for cholesterol-lowering medication: comparison of risk-assessment methods

BACKGROUND

Recommendations for the prescription of lipid-lowering drugs emphasise the importance of an assessment of absolute coronary heart disease (CHD) risk based on all risk factors, rather than simply the serum cholesterol concentration. If, however, the methods recommended for risk assessment are inaccurate, recommended prescribing will not occur. We compared several sets of guidelines for such treatment in a series of patients referred to a lipid clinic, to assess the difference in degree of risk of CHD at which lipid-lowering medication is recommended by each set of guidelines.

METHODS

For a series of 570 patients (50% men) without pre-existing clinical evidence of atherosclerosis referred to a lipid clinic, we compared the algorithms, charts, and tables used by the US National Cholesterol Education Program (NCEP), the joint guidelines of the European Society of Cardiology, the European Atherosclerosis Society, and the European Society of Hypertension, and the report of the UK Standing Medical Advisory Committee with the Framingham risk equation programmed into a computer.

FINDINGS

In 386 patients for whom the NCEP and UK guidelines could be compared, 62% of the men and 72% of the women met NCEP criteria for lipid-lowering medication, whereas only 9% of the men and less than 1% of the women met the UK criteria. The Framingham equation estimated a CHD risk of more than 3% per year in 22% of the men and 7% of the women, which shows that the UK tables underestimated CHD risk. European guidelines could be applied to only 261 patients, and were reasonably accurate in assessment of a CHD risk of 2% per year.

INTERPRETATION

Guidelines for the use of statin treatment in patients with CHD differ in their assessment of CHD risk. The method of risk assessment recommended in future guidelines for CHD prevention should be critically tested in relevant groups of patients.

Role of intestinal mucus on the uptake of latex beads by Peyer's patches and on their transport to mesenteric lymph nodes in rats

BACKGROUND

The effects of N-acetylcysteine (NAC) as a mucolytic agent on the uptake of fluorescent polystyrene microparticles by Peyer's patches, on intestinal permeability, and on subsequent transport to mesenteric lymph nodes (MLNs) were investigated to establish the role of mucus gel layer in this process.

METHODS

Twenty rats were divided into two groups: control (n = 10) and NAC (n = 10). Fluorescent polystyrene latex beads of 3.2+/-0.2 microm in diameter were used as a probe for measuring the previously mentioned parameters. The solution of latex beads (0.1 mL) was injected into a 2-cm length of ileal loop containing Peyer's patches, with 0.1 mL of saline (control group) or with 0.1 mL of NAC solution (NAC group) within 10 cm proximal from the ileocaecal valve. Intestinal loops, portal blood, and neighboring MLNs were taken within 1 hour of injection. Intestinal sections were stained by periodic acid-Schiff reagent. Peyer's patches and MLNs were analyzed for the count of particles by image analysis using a confocal laser scanning microscope.

RESULTS

Morphologically, periodic acid-Schiff positive uniform mucus gel was present in front of Peyer's patches of the control group, and mucus gel layer was disrupted and noncontinuous in the NAC group. The number of particles within Peyer's patches and MLNs in the NAC group was significantly higher than that in the control group (p<.001). Intestinal permeability of latex beads in the NAC group was significantly higher than that in the control group (p<.001).

CONCLUSIONS

These data suggest that the mucus gel layer located in front of Peyer's patches is one of the important factors for the uptake of noxious macromolecules, and this in turn plays a major role on small intestinal permeability and subsequent translocation to MLNs.

Alanyl-glutamine-supplemented parenteral nutrition increases luminal mucus gel and decreases permeability in the rat small intestine

BACKGROUND

Effect of supplemental alanyl-glutamine in standard TPN (S-TPN) on luminal mucus gel and small intestinal permeability was investigated.

METHODS

Thirty Sprague-Dawley rats were divided into group I (n = 10), receiving standard rat diet; group II (n = 10), receiving S-TPN; and group III (n = 10), receiving alanyl-glutamine-supplemented TPN for 1 week. After 1 week, fluorescein isothiocyanate (FITC)-dextran was injected into the small intestine of the rats, and they were killed. A small intestinal sample and portal blood were obtained for morphologic and functional analysis of mucus gel and intestinal permeability.

RESULTS

In group II, thickness and optical density of mucus gel per millimeter serosal length of intestine were significantly lower than group I (p<.001) and were significantly higher in group III than in group II (p<.001). The number of goblet cells in the villi and in the crypt of the small intestine was significantly lower in group II than in group I (p<.001) and was significantly higher in group III than in group II (p<.001), with the exception of the villi of jejunum. Villous and crypt surface area per millimeter serosal length of intestine was significantly lower in group II than in group I (p<.001) and was significantly higher in group III than in group II (p<.001). Small intestinal permeability to FITC-dextran was significantly higher in group II than in group I (p<.001) and was significantly lower in group III than in group II (p<.001). Glucosamine synthetase level was significantly higher in group III than in group I and ileum of group II (p<.001).

CONCLUSIONS

Alanyl-glutamine-supplemented TPN prevents a decrease in mucus gel and an increase in small intestinal permeability associated with S-TPN.

Gene expression profiling of alveolar rhabdomyosarcoma with cDNA microarrays

Several forms of human sarcoma, lymphoma, and leukemia are characterized by somatically acquired chromosome translocations that result in fusion genes that encode chimeric transcription factors with oncogenic properties. We have used cDNA microarrays containing 1238 cDNAs to investigate the gene expression profile of a group of seven alveolar rhabdomyosarcoma (ARMS) cell lines characterized by the presence of the PAX3-FKHR fusion gene. Using the method of multidimensional scaling to represent the relationships among the cell lines in two-dimensional Euclidean space, we determined that ARMS cells show a consistent pattern of gene expression, which allows the cells to be clustered together. By searching across the seven ARMS cell lines, we found that 37 of 1238 genes were most consistently expressed in ARMS relative to a reference cell line. Only three of these genes have been previously reported to be expressed in ARMS. Among these 37 were genes related to both primary (PAX3-FKHR) and secondary (CDK4) genetic alterations in ARMS. These results in ARMS demonstrate the potential of cDNA microarray technology to elucidate tumor-specific gene expression profiles in human cancers.

Zinc deficiency enhances interleukin-1alpha-induced metallothionein-1 expression in rats

This study investigated whether interleukin-1alpha-induced metallothionein gene expression is affected by zinc deficiency. Weaning male rats were fed a zinc-deficient (ZD) diet (2 mg zinc/kg) or a zinc-supplemented diet [50.8 mg zinc/kg; controls for the diet included pair-fed (PF) and ad libitum consumption groups (AL)] for 4 wk. All rats except those that served as controls for interleukin-1alpha administration, (injected with vehicle and killed at 0 h) were then injected subcutaneously with interleukin-1alpha (2 x 10(7) units/kg body wt) and killed at 3, 6, 12, 24 and 72 h after the injection. Compared with AL and/or PF rats, zinc depletion significantly reduced zinc concentrations in plasma and liver but not in kidney or intestine, and significantly reduced hepatic, renal, and intestinal metallothionein-1 mRNA levels analyzed by competitive reverse transcription-polymerase chain reaction (RT-PCR). Interleukin-1alpha injection reduced plasma zinc concentration and enhanced liver zinc concentration, but did not affect zinc levels in kidney or intestine. Metallothionein-1 mRNA was significantly elevated by interleukin-1alpha in liver, kidney and intestine of all groups; the levels in liver and kidney of ZD rats 6 h after the injection were significantly higher than those of AL or PF rats. Liver metallothionein protein levels were enhanced after interleukin-1alpha injection in both AL and ZD rats. Semiquantitative RT-PCR revealed significantly higher hepatic levels of interleukin-1 receptor type-I mRNA in ZD rats than in AL and PF rats but no differences in renal or intestinal tissues among groups before interleukin-1alpha challenge. In conclusion, zinc deficiency induces upregulation of metallothionein-1 gene expression in response to interleukin-1alpha challenge in rats.

Detection of gains and losses in 18 meningiomas by comparative genomic hybridization

Comparative genomic hybridization (CGH) was used to examine gains and losses in 18 meningioma tumors that had been previously analyzed for loss of heterozygosity (LOH) at 22q12. Partial or complete losses were seen by CGH in only 9 of 18 cases on chromosome 22. This compares with 11 of 18 losses of single or more loci by LOH. The discrepancy in these results in probably explained by the increased sensitivity of LOH by using microsatellite markers that are able to detect small deletions, whereas losses on the order of 10-15 megabases are required for confident identification by CGH. There was no consistent pattern of gains or losses by CGH, including those tumors that lacked LOH at 22q12. In one tumor of interest in which CGH and LOH studies failed to demonstrate loss on chromosome 22, CGH identified an area of amplification at 17q22-23.

3-Nitrotyrosine in the proteins of human plasma determined by an ELISA method

The modification of tyrosine residues in proteins to 3-nitrotyrosine by peroxynitrite or other potential nitrating agents has been detected in biological systems that are subject to oxidative stress. A convenient semi-quantitative method has been developed to assay nitrated proteins in biological fluids and homogenates using a competitive ELISA developed in our laboratory. This assay selectivity detected 3-nitro-l-tyrosine residues in a variety of peroxynitrite-treated proteins (BSA, human serum albumin (HSA), alpha1-antiprotease inhibitor, pepsinogen and fibrinogen) and also in a nitrated peptide, but had a low affinity for free 3-nitro-L-tyrosine and 3-chloro-L-tyrosine. The IC50 values for the inhibition of antibody binding by different nitrated proteins were in the range 5-100 nM, suggesting that the antibody discriminated between nitrotyrosine residues in different environments. The presence of nitrotyrosine in plasma proteins was detected by Western blot analysis and quantified by the ELISA. A concentration of 0. 12+/-0.01 microM nitro-BSA equivalents was measured in the proteins of normal plasma which was increased in peroxynitrite-treated plasma and was elevated in inflammatory conditions. HSA and low-density lipoprotein (LDL) isolated from plasma contained 0.085+/-0.04 and 0. 03+/-0.006 nmol nitro-BSA equivalents/mg protein, respectively. Comparison of the level of nitration in peroxynitrite-treated HSA and LDL in the presence and absence of plasma indicates that nitration and presumably oxidation is inhibited by plasma antioxidants. The presence of nitrotyrosine in LDL is consistent with previous reports implicating peroxynitrite in the oxidative modification of lipoproteins and the presence of a low concentration of oxidized LDL in the blood.

Induction of nitric oxide synthase in rat intestine by interleukin-1alpha may explain diarrhea associated with zinc deficiency

Synthesis of inducible nitric oxide synthase (iNOS) in the intestine may result in local tissue damage. We investigated whether a challenge with interleukin-1alpha could give rise to intestinal iNOS expression and diarrhea in rats of differing zinc status. Weaning male rats were fed a zinc-deficient (ZD) diet (2 mg zinc/kg) for 4 wk to induce zinc deficiency or a zinc-supplemented diet [50.8 mg zinc/kg; controls, including pair-fed (PF ) and ad libitum (AL) consumption groups], and then subcutaneously injected with interleukin-1alpha (2 x 10(7) units/kg body wt). Without the interleukin-1alpha challenge, ZD rats had significantly lower plasma zinc concentration than the other groups. Intestinal metallothionein-1 mRNA abundance was lower in ZD rats than in AL rats. iNOS was expressed in the intestine of ZD rats but not in the others. None of the rats experienced diarrhea during the feeding period. Interleukin-1alpha led to a reduction in plasma zinc concentration, enhancement in intestinal metallothionein-1 mRNA levels, and expression of the intestinal iNOS gene in all groups. However, the abundance of iNOS mRNA was significantly higher in ZD rats than in the other groups. The presence of iNOS protein was demonstrated by immunohistochemical staining in the intestine of ZD rats that had been treated with interleukin-1alpha 12 h earlier. In addition, diarrhea occurred in most of the ZD rats and some of the PF rats but not in AL rats after interleukin-1alpha treatment. We conclude that ZD rats respond to interleukin-1alpha challenge more severely than controls, reflected by a more marked and prolonged iNOS expression and a greater incidence of diarrhea.

Correlation of histologic subtypes of primary basal cell carcinoma and number of Mohs stages required to achieve a tumor-free plane

BACKGROUND

Certain histologic subtypes of basal cell carcinoma (BCC) behave more aggressively and require more aggressive treatment.

OBJECTIVE

The aim of this study was to see whether certain subtypes of BCC require more Mohs stages to achieve tumor-free margins.

METHODS

A retrospective study of 342 primary BCCs treated with Mohs micrographic surgery (MMS) was performed identifying the histologic subtype of BCC present and the number of stages required to clear the tumor.

RESULTS

The aggressive subtypes (infiltrative, morpheaform, micronodular, and mixed) were most frequently found when high numbers of Mohs stages were required for cure.

CONCLUSION

The more aggressive subtypes of BCC require more MMS stages to achieve tumor-free margins, which is consistent with the concept that these subtypes usually require more aggressive treatment from the start.

Circulating anti-(xanthine oxidoreductase) antibodies in healthy human adults

Levels of free anti-(xanthine oxidoreductase) (XOR) antibodies in the serum of normal healthy human subjects were determined, using both human and bovine enzyme as antigen, in an enzyme-linked immunosorbent assay (ELISA). Levels of IgM class anti-(human XOR) antibodies were found to be particularly high (mean values representing approximately 3% of total IgM) and to be significantly higher than levels of IgM anti-(bovine XOR) antibodies, indicating that endogenous XOR, rather than ingested bovine milk XOR, is the immunogen. IgM anti-XOR antibody levels were significantly higher in women under 50 years than in age-matched men, or in older women. Levels of IgG class anti-XOR antibodies were much lower and showed no correlation with gender or age. Affinity-purified anti-(human XOR) antibodies only partially inhibited enzymic activities of XOR. The majority of both IgM and IgG anti-(human XOR) antibodies in serum occurred as immune complexes, suggesting that the specific antibodies have a protective role in removing potentially damaging XOR from the circulation.

Developmental changes in distribution of the mucous gel layer in rat small intestine

The intraluminal mucous gel layer across the small intestine of rats aged 3 days, 1, 2, 4 and 6 weeks (n=10x5) was studied to investigate its postnatal development. Celloidin stabilisation of dried cryostat sections of small intestine, with the luminal contents, preserved the intraluminal mucous gel layer for staining by the periodic acid-Schiff reaction. Morphological differences in the mucous gel, between the villi of the small intestine, in rats of several postnatal ages were observed, most notably after the age of 2 weeks. The adhesive mucous gel layer, covering the intestinal epithelium in the small intestine, appears to undergo rapid development after weaning.

Total parenteral nutrition increases uptake of latex beads by Peyer's patches

BACKGROUND

Dysfunction of the intestinal barrier, as evidenced by increased intestinal permeability and bacterial translocation, has been reported under total parenteral nutrition (TPN). However, the role of Peyer's patches on the intestinal barrier in TPN is not well understood. We investigated whether TPN alters the uptake of microparticles by the follicle-associated epithelium of Peyer's patches.

METHODS

Twenty rats were divided into two groups, a control group and a TPN group. Fluorescent polystyrene latex beads, 3.2 +/- 0.2 microns in diameter, were used as a probe for measuring the uptake by Peyer's patches. After 1 week of consuming either the control or TPN diet, rats were killed. On the day of killing, 0.1 mL of latex beads solution was injected into a 1-cm length of ileal loop, within 10 cm of the ileocecal valve. Samples were taken after 30 minutes of injection, sectioned by cryostat, and then viewed under a fluorescent microscope. Follicle-associated epithelial length and particles were counted using a confocal laser scanning microscope. The number of particles within each compartment was standardized per unit length of epithelium of Peyer's patches.

RESULTS

Particle numbers within Peyer's patch dome of the TPN group were significantly increased compared with those of the control group (p < .01).

CONCLUSIONS

These data suggest that dysfunction of the intestinal barrier in TPN might be associated with a change of uptake by Peyer's patches.

Dermal grafting for a patient with scleroderma. Case report

Scleroderma is a connective tissue disorder which includes fibrosis of the skin. Facial skin contraction leads to loss of forehead, periorbital, and nasolabial wrinkling and at the same time causes radial furrows around the contracted oral opening (microstomia). The lips become retracted. We describe a 41 year old lady whose upper lip was treated by free dermal graft and injection of fat to improve her perioral aesthetic appearance. The skin was taken from the right submammary fold and the fat was obtained from the abdomen by liposuction. Excess fat was stored in a sterile container at -70 degrees C for future use. The patient made a satisfactory recovery and has asked for her lower lip to be treated in the same way.

Developmental changes in distribution of the mucous gel layer and intestinal permeability in rat small intestine

BACKGROUND

From the developmental aspects, the distribution of fluorescein isothiocyanate dextran 70,000 (FTTC-dextran) and mucous gel across the lumen of small intestine was observed as an investigation into the role of mucous gel on intestinal permeability. Furthermore, the effect of N-acetyl cysteine (NAC), a mucolytic agent, on intestinal permeability was examined.

METHODS

In suckling and weaned rats, FTTC-dextran (750 mg/kg body wt) was gavage-fed. After 3 hours, blood samples were taken by cardiac puncture to analyze plasma FTTC-dextran by fluorescence spectrometry. Samples of small intestine with luminal contents were frozen and sectioned in a cryostat for fluorescence microscopy; the same sections were placed in a 0.2% celloidin solution to preserve mucous gel and were stained by periodic acid-Schiff reaction for light microscopy. In weaned rats, intestinal permeability was examined with different concentrations of intraluminally instilled NAC.

RESULTS

The plasma level of FTTC-dextran showed a significant increase (p < .01) in suckling rats compared with the weaned rats. Morphologic findings were similar in both the jejunum and ileum: The spaces between villi were not entirely filled with mucus but filled with FTTC-dextran in suckling rats, whereas the spaces were filled with mucus and not filled with FTTC-dextran in weaned rats. Intestinal permeability in groups with NAC were significantly higher (p < .01) than that in group without NAC.

CONCLUSIONS

These results suggest that an increase in the mucous gel layer that coats the epithelial lining according to the maturation of the gastrointestinal tract is one of the most important factors for a restriction in intestinal permeability.

Palmar bands in rheumatoid arthritis and other chronic conditions of the upper limb

Palmar prolapse of the flexor tendons as a result of attenuation of the A1 and A2 pulleys occurs in rheumatoid arthritis and other conditions in which the joints of the fingers are chronically flexed. The flexor tendons may be palpable and sometimes visible as longitudinal bands crossing the palm. This can lead to confusion with the palmar bands of Dupuytren's disease. These bands are illustrated in a small series of patients and a serious complication of a misdiagnosis of Dupuytren's disease is presented. The pathogenesis of these palmar bands in rheumatoid arthritis is discussed.

Adhesive mucous gel layer and mucus release as intestinal barrier in rats

BACKGROUND

Although it has been reported that total parenteral nutrition induces an increased intestinal permeability and a decreased mucous gel layer covering the intestinal epithelium, the role of mucous gel on intestinal permeability has not been well understood. We examined the in vivo effects of N-acetyl cysteine (NAC) as mucolytic agent and colchicine as suppressant of the mucus production on the intestinal transmission of fluorescein isothiocyanate dextran 70,000 (FITC-dextran).

METHODS

Rats were divided into four groups. In each group, FITC-dextran (750 mg/kg) with or without NAC (3000 mg/kg) was injected into the small intestinal lumen 3 hours after intraperitoneal injection of saline or colchicine (Col, 10 mg/kg). Thirty minutes after injection of FITC-dextran, blood samples were taken from portal vein to analyze plasma fluorescein concentration by fluorescence spectrometry. Samples of small intestine were sectioned in a cryostat for fluorescence microscopy, and the identical sections were stained by periodic acid-Schiff reaction.

RESULTS

Plasma FITC-dextran level in NAC group was higher than that in control group (p < .01), that in Col + NAC group was higher than that in Col group (p < .01) and that in Col + NAC group was higher than that in NAC group (p < .05). The spaces between villi were filled with mucous gel in the control and Col groups, whereas those were not entirely filled with mucous gel in NAC and Col + NAC groups. FITC-dextran and mucous gel showed complementary distribution in all rats. The villous interstitial edema was recognized in NAC group and the villi were disrupted in Col + NAC group.

CONCLUSIONS

These results suggest that intestinal permeability is possibly affected not only by the mucous gel covering the intestinal epithelium but also by mucus release from goblet cells of the small intestine.

The management of ectropion using the tarsoconjunctival composite graft

OBJECTIVE

To demonstrate the technique, advantages, and results of autogenous tarsal grafts in the treatment of ectropion with lower eyelid retraction.

DESIGN

Fourteen patients treated with autogenous tarsal grafts were evaluated. Follow-up ranged from 6 to 30 months (mean follow-up, 10 months).

SETTING

All patients were treated at the University of Kansas Medical Center, Kansas City, December 1990 through June 1993.

PATIENTS

Of 14 patients with ectropion who were treated with this technique, nine had facial nerve paralysis, three had had previous periorbital trauma resulting in cicatricial ectropion, one patient had orbital and congenital lower lid fibrosis, and one patient had Graves' ophthalmopathy with lower lid retraction.

INTERVENTION

All patients underwent autogenous tarsal grafting. Eleven patients also underwent combined laterocanthal suspension (tarsal tongue technique). Seven patients underwent associated upper lid gold weight loading. One patient underwent a medial canthopexy.

RESULTS

All patients had marked improvement functionally and cosmetically. One patient had slight under-correction. Results have remained stable for over 2 years.

CONCLUSIONS

Autogenous tarsal grafts aid in the long-term stability of lower lid ectropion repair. Autogenous tarsal grafting has distinct advantages over other described techniques. When treating paralytic ectropion, other rehabilitative techniques must be additionally employed.

Predictors of postnatal head molding in very low birth weight infants

This study examined potential predictors of postnatal head molding in very low birth weight (VLBW) infants. Occipital-frontal circumference (OFC) and anterior-posterior (AP) and biparietal (BP) diameter measurements were obtained on 144 premature infants with birth weights of less than 1,500 gm. Measurements were obtained at four days of age (baseline) and weekly until discharge. Increasing gestational age, higher birth weight, and delivery by cesarean section predicted larger OFC at three weeks of life. Only baseline AP:BP measurements significantly predicted AP:BP measurements at week 3 and 5. Within-group t-tests indicated that the severity of head molding (as indicated by AP:BP ratio) increased throughout the first six weeks of life. Results indicate that postnatal head molding can be reliably predicted and that neonates with higher AP:BP ratios at birth are at greater risk for continued narrow, elongated head shape.

CT-guided fine needle aspiration biopsy in the diagnosis of mediastinal tuberculosis

Twenty-two patients with mediastinal tuberculosis were reviewed. The most common symptoms were chest pain, cough, fever, and weight loss. Results of the physical examination were unremarkable. The chest radiographs of all 22 patients showed abnormal mediastinum with no evidence of extramediastinal disease. Most (62%) had right-sided paratracheal lymphadenopathy. Mantoux skin test was positive (> 15 mm) in all patients, whereas sputum smears and cultures for acid-fast bacilli were negative. Computed tomographic (CT) guided fine needle aspiration biopsies (FNAB) were performed in 12 patients using 22- to 25-gauge needles. Ten patients had fiberoptic bronchoscopic (FOB) examination with brushings and biopsies. Mediastinoscopy (n = 8) or thoracotomy (n = 6) was performed in patients where either FNAB or FOB was not diagnostic or where lymphoma was suspected clinically. The rates of true-positive diagnoses were 20%, 66%, 75%, and 100% for FOB, FNAB, mediastinoscopy, and thoracotomy, respectively. The rate of false-negative for FNAB was 34%. Only one patient developed nonsignificant pneumothorax after FNAB. These findings suggest that CT-guided FNAB is a useful and safe procedure and should be considered in the initial evaluation of patients suspected of having mediastinal tuberculosis.

The biphasic mechanism of blood flow during cardiopulmonary resuscitation: a physiologic comparison of active compression-decompression and high-impulse manual external cardiac massage

STUDY OBJECTIVE

Dismal survival in patients receiving standard manual CPR provided the rationale for the investigation of alternate methods of closed-chest circulatory support. Active compression-decompression (ACD) and high-impulse CPR are alternatives to standard manual CPR. This study was designed to test the hypothesis that ACD CPR provides superior cardiopulmonary hemodynamics due to an active decompression phase when compared with high-impulse manual CPR.

PARTICIPANTS

Hemodynamics were studied during ACD and high-impulse CPR in eight adult beagles.

DESIGN

Four animals were chronically instrumented and four were studied acutely. In an additional four animals, ACD was compared with sham ACD CPR. Each CPR technique was performed sequentially for 2 minutes, in random order, at a rate of 120, 50% duty cycle, and 1.5 to 2.0 in of compression depth. Measurements obtained included aortic, right atrial, left ventricular, and coronary perfusion pressures (in mm Hg); pulmonary artery flow, and left ventricular dimension.

RESULTS

ACD maximized cardiopulmonary hemodynamics, including coronary perfusion pressure and stroke volume, compared with both high-impulse manual and sham ACD CPR. ACD CPR also increased left ventricular pressure change per unit time during decompression, and these changes correlated well with left ventricular volume changes.

CONCLUSION

In the intact dog, ACD CPR generates physiologically and statistically superior hemodynamics when compared with high-impulse manual CPR. Improved blood flow seems to be related to more efficient ventricular filling and emptying. These findings emphasize the biphasic nature of CPR and the importance of active decompression.

Total lung collapse after pulmonary infarction

A case is presented of total lung collapse secondary to intrabronchial blood clot as a complication of pulmonary infarction. The blood clot was removed at bronchoscopy with complete re-expansion of the lung.

Risk factors for chronic obstructive lung disease in Saudi Arabia

Based on the clinical impression of a relatively high number of non smoking women with COPD at a tertiary care facility in Saudi Arabia, we performed a case-control study to reveal possible risk factors. Our hypothesis was that the extensive use of incense burners among Saudis was a risk factor of COPD. Fifty consecutive patients with COPD and 71 healthy controls were questioned about risk factors of COPD. As expected more COPD-men than control men were smokers. Very few women smoked. We found no difference in the use of incense burners between cases and controls. On the other hand, two-thirds of the COPD-women and only 1/20 of the control women had been exposed to indoor open fire for more than 20 yr (P < 0.05). Accordingly, indoor exposure to open fire of wood or biomass seems to be a risk factor of COPD among Saudi women.

Precise repair of orbital maxillary zygomatic fractures

OBJECTIVE

To demonstrate the techniques, advantages, indications, and potential pitfalls of the transconjunctival approach with lateral canthotomy, sublabial approach, and coronal approach in the treatment of complex trimalar fracture with associated blow-out fractures.

DESIGN

All patients diagnosed as having complex trimalar fractures with or without blow-out treated by either of us over a 2-year period were included. Follow-up ranged from a minimum of 6 months to 2 years.

SETTING

All patients were treated with December 1989 to December 1991 at either Louisiana State University Medical Center, Shreveport, or University of Kansas Medical Center, Kansas City.

PATIENTS

Eighteen patients with complex trimalar fractures were included in this study. Eight patients had associated orbital blow-out fractures. Simple isolated arch fractures were excluded.

INTERVENTION

All subjects underwent a transconjunctival approach with lateral canthotomy. Seven subjects also had associated sublabial flaps. Five patients required hemicoronal or coronal approaches.

RESULTS

There were seven minor complications. Ninety-three percent (14/15 [three didn't respond to the survey]) of patients surveyed were either very satisfied or satisfied with their functional and cosmetic results.

CONCLUSION

The management of complex trimalar fracture with blow-outs is greatly facilitated by the rational application of the described techniques.

Castleman's disease of the chest. Magnetic resonance imaging features

The value of magnetic resonance imaging (MRI) in the evaluation of vascular abnormalities in the chest is well established. To our knowledge, however, MRI in Castleman's disease of the chest had not been reported previously. We present a case of Castleman's disease of hyaline vascular type involving the pulmonary hilum where MRI was equal to computed tomography in showing the extent of the disease, but was more informative in demonstrating its relationship with vascular structures.

Pulmonary metastases of gestational trophoblastic tumor. Risk factors for early respiratory failure

Between January 1980 and December 1990, 75 (57.3%) of 131 patients with metastatic gestational trophoblastic tumor had pulmonary metastases detected on plain chest roentgenography at the King Faisal Specialist Hospital and Research Centre. Pulmonary involvement was commonly extensive, with 32 (42.7%) patients having > 10 pulmonary metastases and 45 (60%) patients having a pulmonary lesion > 5 cm in diameter. Greater than 50% lung opacification, mediastinal involvement and pleural effusion were present in 25 (33.3%), 25 (33.3%) and 36 (48%) patients, respectively. Eight (10.7%) patients developed early respiratory failure requiring mechanical ventilation within one month of presentation. The development of early respiratory failure was significantly associated with the presence of dyspnea, anemia, clinical pulmonary hypertension, cyanosis, > 50% lung opacification, mediastinal involvement and bilateral pleural effusion. Because all patients requiring mechanical ventilation died, the use of extracorporeal perfusion should be considered in patients with early respiratory failure.

A new technique for placement of central venous catheters in small infants

The delivery of total parenteral nutrition to premature infants has been a major advance in neonatal intensive care. Ideally, total parenteral nutrition fluids should be given through a central venous catheter, but insertion of such a catheter may be a very difficult procedure in small neonates. We describe a new technique that improves the success rate of central venous catheterization in premature infants.

The effects of a pressure relief mattress on postnatal head molding in very low birth weight infants

Very low birth weight (VLBW) infants often develop postnatal head molding (PHM)--an elongation of the skull--when a standard, firm mattress is used. This study was undertaken to determine if a pressure relief mattress (PRM) might reduce the severity of PHM. One hundred twenty-eight infants (birth weight range 567-1,490 gm, mean 1,084; gestational age range 24-36 weeks, mean 28.5) with no congenital or acquired anomalies affecting head growth were randomly assigned to a control group (standard, firm mattress) or a study group (PRM). Study infants were placed on the PRM within 72 hours of birth. Occipitofrontal circumference (OFC) and anterior-posterior (AP) and biparietal (BP) diameters were measured at day four, seven, and then at one week intervals of life until the infant reached 2,000 gm or was discharged. An electronic digital caliper with an accuracy of 0.025 mm was used to obtain the AP and BP measurements. T-tests revealed no significant differences in head shape between the two groups. In conclusion, the pressure relief mattress did not reduce PHM in VLBW infants.

Tumor lysis syndrome complicating treatment of widespread metastatic abdominal rhabdomyosarcoma

In this paper we describe a 9-year-old girl with abdominal embryonal rhabdomyosarcoma. She had ascites and widespread metastatic disease at presentation and was oliguric but had a normal creatinine. Following the start of chemotherapy she developed acute renal failure secondary to the tumor lysis syndrome, requiring hemodialysis, and had considerable myelotoxicity.

Sarcoidosis in native Saudis

Sarcoidosis is believed to be rare in Saudi Arabia. We report twenty cases of sarcoidosis among native Saudis followed-up at our tertiary care centre. The majority (55%) of these patients were referred as either tuberculosis or lymphoma. Twelve out of twenty patients had been or were being treated for pulmonary tuberculosis at the time of presentation. The clinical presentation of these patients was similar to the western pattern of disease with some differences such as severe constitutional symptoms (52%), relative frequent eye involvement (35%) and common occurrence of stage II changes on chest film (70%). Mantoux skin test was negative in nineteen patients (95%). Histological evidence of non-caseating granulomata was obtained in 19 patients. A positive correlation (p < 0.034) between constitutional symptoms and Angiotensin Converting Enzyme (ACE) levels was noted. Thirteen patients (65%) were treated with oral steroids while topical ophthalmic steroids were used in seven patients (35%). Functional and radiographic deterioration was observed in four patients (20%). Three patients went into respiratory failure including a patient who developed Hodgkin's lymphoma six years after the diagnosis of sarcoidosis. The epidemiology of sarcoidosis among native Saudis requires further studies.

Neutropenic enterocolitis associated with Clostridium tertium

A 15 year old boy being treated for relapsed acute lymphoblastic leukaemia developed severe diarrhoea and abdominal pain which worsened despite empirical antibiotic treatment. A right hemicolectomy was performed. The caecum and ascending colon showed changes typical of neutropenic enterocolitis. Clostridium tertium was isolated from faeces, blood cultures, and from the resected gut wall, with no evidence of other organisms capable of causing such a condition. As far as is known, this is the first reported case in which neutropenic enterocolitis has been associated with well documented C tertium infection, an organism previously described as a cause of bacteraemia in neutropenic patients.

Drug resistance of Mycobacterium tuberculosis in Karachi, Pakistan

We determined the primary and secondary resistance of isolates of M. tuberculosis to the standard antituberculous drugs in Karachi (Pakistan). Primary resistance to one or more anti-tuberculous drugs was found in 17% of 123 isolates of M. tuberculosis (obtained from patients with no history of previous treatment for tuberculosis). Secondary resistance was found in 36% of 33 isolates (obtained from individuals who had received anti-tuberculous treatment in the past). The drug to which organisms were most commonly resistant was isoniazid (11% primary resistance, 30% secondary resistance). Fifteen per cent of isolates obtained from previously-studied patients showed secondary resistance to rifampicin. We discuss the importance of these findings for tuberculosis treatment and control.

Marriage delays in Pakistan: analysis of selected view points

The authors explore reasons for the observed increases in marriage age in Pakistan. "Using anecdotal data from urban Pakistan, an attempt is made in this paper to analyse the perceived reasons that cause delay in marriage as well as some suggestions made by the respondents of this study to overcome the delay if necessary. In [pursuing] this objective, regional and gender variations with regard to reasons and suggestions are discussed."

Malignant mesothelioma: King Faisal Specialist Hospital and Research Centre experience

Ten cases of malignant mesothelioma were diagnosed and treated at the King Faisal Specialist Hospital and Research Centre over a ten year period from 1977 to 1987. Seven of these cases were referred from the Southern Province and were clustered in the Al-Baha and Najran districts. In only one case (a plumber from Taif) was there the likelihood of occupation exposure. None of the patients had interstitial changes or pleura plaques on chest x-ray. Epidemiological studies are warranted to establish the etiology of mesothelioma in the Southern region of Saudi Arabia.