A role for nitric oxide in the control of breathing in zebrafish (Danio rerio)

Nitric oxide (NO) is a gaseous neurotransmitter, which in adult mammals, modulates the acute hypoxic ventilatory response; its role in the control of breathing in fish during development is unknown. We addressed the interactive effects of developmental age and NO in the control of piscine breathing by measuring the ventilatory response of zebrafish (Danio rerio) adults and larvae to NO donors and by inhibiting endogenous production of NO. In adults, sodium nitroprusside (SNP), a NO donor, inhibited ventilation; the extent of the ventilatory inhibition was related to the pre-existing ventilatory drive, with the greatest inhibition exhibited during exposure to hypoxia (PO2=5.6 kPa). Inhibition of endogenous NO production using L-NAME supressed the hypoventilatory response to hyperoxia, supporting an inhibitory role of NO in adult zebrafish. Neuroepithelial cells, the putative oxygen chemoreceptors of fish, contain neuronal nitric oxide synthase (nNOS). In zebrafish larvae at 4 days post fertilization, SNP increased ventilation in a concentration-dependent manner. Inhibition of NOS activity with L-NAME or knockdown of nNOS inhibited the hypoxic (PO2=3.5 kPa) ventilatory response. Immunohistochemistry revealed the presence of nNOS in the NECs of larvae. Taken together, these data suggest that NO plays an inhibitory role in the control ventilation in adult zebrafish, but an excitatory role in larvae.

Long-term efficacy of NASHA Dx injection therapy for treatment of fecal incontinence

BACKGROUND

Injectable bulking treatment for fecal incontinence (FI) is intended to expand tissue in the anal canal and prevent fecal leakage. Use of injectable bulking agents is increasing because it can be performed in an outpatient setting and with low risk for morbidity. This study evaluated the long-term (36-month) clinical effectiveness and safety of injection of non-animal stabilized hyaluronic acid/dextranomer (NASHA Dx) on FI symptoms.

METHODS

In a prospective multicenter trial, 136 patients with FI received the NASHA Dx bulking agent. Treatment success defined as a reduction in number of FI episodes by 50% or more compared with baseline (Responder50 ). Change from baseline in Cleveland Clinic Florida Fecal Incontinence Score (CCFIS) and Fecal Incontinence Quality of Life Scale (FIQL), and adverse events were also evaluated.

KEY RESULTS

Successful decrease in symptoms was achieved in 52% of patients at 6 months and this was sustained at 12 months (57%) and 36 months (52%). Mean CCFIS decreased from 14 at baseline to 11 at 36 months (p < 0.001). Quality-of-life scores for all four domains improved significantly between baseline and 36 months of follow-up. Severe adverse events were rare and most adverse events were transient and pertained to minor bleeding and pain or discomfort.

CONCLUSIONS & INFERENCES

Submucosal injection of NASHA Dx provided a significant improvement of FI symptoms in a majority of patients and this effect was stable during the course of the follow-up and maintained for 3 years.

Cardiac responses to hypercapnia in larval zebrafish (Danio rerio): the links between CO2 chemoreception, catecholamines and carbonic anhydrase

The ontogeny of carbon dioxide (CO2) sensing in zebrafish (Danio rerio) has not been examined. In this study, CO2-mediated increases in heart rate were used to gauge the capacity of zebrafish larvae to sense CO2. CO2 is thought to be detected via neuroepithelial cells (NECs), which are homologous to mammalian carotid body glomus cells. Larvae at 5 days post-fertilization (d.p.f.) exhibited tachycardia when exposed for 30 min to 0.75% CO2 (~5.63 mmHg); at 7 d.p.f., tachycardia was elicited by 0.5% CO2 (~3.75 mmHg). Based on pharmacological evidence using β-adrenergic receptor (β-AR) antagonists, and confirmed by β1-AR translational gene knockdown using morpholinos, the reflex tachycardia accompanying hypercapnia was probably mediated by the interaction of catecholamines with cardiac β1 receptors. Because the cardiac response to hypercapnia was abolished by the ganglionic blocker hexamethonium, it is probable that the reflex cardio-acceleration was mediated by catecholamines derived from sympathetic adrenergic neurons. Owing to its likely role in facilitating intracellular acidification during exposure to hypercapnia, it was hypothesized that carbonic anhydrase (CA) is involved in CO2 sensing, and that inhibition of CA activity would blunt the downstream responses. Indeed, the cardiac response to hypercapnia (0.75% CO2) was reduced in fish at 5 d.p.f. exposed to acetazolamide, a CA inhibitor, and in fish experiencing zCAc (CA2-like a) knockdown. Successful knockdown of zCAc was confirmed by CA activity measurements, western blotting and immunocytochemistry. Co-injection of embryos with zCAc morpholino and mRNA modified at the morpholino binding site restored normal levels of CA activity and protein levels, and restored (rescued) the usual cardiac responses to hypercapnia. These data, combined with the finding that zCAc is expressed in NECs located on the skin, suggest that the afferent limb of the CO2-induced cardiac reflex in zebrafish larvae is initiated by coetaneous CO2-sensing neuroepithelial cells.

The role of hydrogen sulphide in the control of breathing in hypoxic zebrafish (Danio rerio)

The current study investigated the role of hydrogen sulphide (H2S) in oxygen sensing, intracellular signalling and promotion of ventilatory responses to hypoxia in adult and larval zebrafish (Danio rerio). Both larval and adult zebrafish exhibited a dose-dependent increase in ventilation to sodium sulphide (Na2S), an H2S donor. In vertebrates, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE) are enzymes that catalyse the endogenous production of H2S. In adult zebrafish, inhibition of both CBS and CSE with aminooxyacetate (AOA) and propargyl glycine (PPG) blunted or abolished the hypoxic hyperventilation, and the addition of Na2S to the water partially rescued the effects of inhibiting endogenous H2S production. In zebrafish larvae (4 days post-fertilization), gene knockdown of either CBS or CSE using morpholinos attenuated the hypoxic ventilatory response. Furthermore, the intracellular calcium concentration of isolated neuroepithelial cells (NECs), which are putative oxygen chemoreceptors, increased significantly when these cells were exposed to 50 μm Na2S, supporting a role for H2S in Ca(2+)-evoked neurotransmitter release in these cells. Finally, immunohistochemical labelling showed that NECs dissociated from adult gill contained CBS and CSE, whereas cutaneous NECs in larval zebrafish expressed only CSE. Taken together, these data show that H2S can be produced in the putative oxygen-sensing cells of zebrafish, the NECs, in which it appears to play a pivotal role in promoting the hypoxic ventilatory response.

Genotype List String: a grammar for describing HLA and KIR genotyping results in a text string

Knowledge of an individual's human leukocyte antigen (HLA) genotype is essential for modern medical genetics, and is crucial for hematopoietic stem cell and solid-organ transplantation. However, the high levels of polymorphism known for the HLA genes make it difficult to generate an HLA genotype that unambiguously identifies the alleles that are present at a given HLA locus in an individual. For the last 20 years, the histocompatibility and immunogenetics community has recorded this HLA genotyping ambiguity using allele codes developed by the National Marrow Donor Program (NMDP). While these allele codes may have been effective for recording an HLA genotyping result when initially developed, their use today results in increased ambiguity in an HLA genotype, and they are no longer suitable in the era of rapid allele discovery and ultra-high allele polymorphism. Here, we present a text string format capable of fully representing HLA genotyping results. This Genotype List (GL) String format is an extension of a proposed standard for reporting killer-cell immunoglobulin-like receptor (KIR) genotype data that can be applied to any genetic data that use a standard nomenclature for identifying variants. The GL String format uses a hierarchical set of operators to describe the relationships between alleles, lists of possible alleles, phased alleles, genotypes, lists of possible genotypes, and multilocus unphased genotypes, without losing typing information or increasing typing ambiguity. When used in concert with appropriate tools to create, exchange, and parse these strings, we anticipate that GL Strings will replace NMDP allele codes for reporting HLA genotypes.

Heterogeneous conservation of Dlx paralog co-expression in jawed vertebrates

Background

The Dlx gene family encodes transcription factors involved in the development of a wide variety of morphological innovations that first evolved at the origins of vertebrates or of the jawed vertebrates. This gene family expanded with the two rounds of genome duplications that occurred before jawed vertebrates diversified. It includes at least three bigene pairs sharing conserved regulatory sequences in tetrapods and teleost fish, but has been only partially characterized in chondrichthyans, the third major group of jawed vertebrates. Here we take advantage of developmental and molecular tools applied to the shark Scyliorhinus canicula to fill in the gap and provide an overview of the evolution of the Dlx family in the jawed vertebrates. These results are analyzed in the theoretical framework of the DDC (Duplication-Degeneration-Complementation) model.

Results

The genomic organisation of the catshark Dlx genes is similar to that previously described for tetrapods. Conserved non-coding elements identified in bony fish were also identified in catshark Dlx clusters and showed regulatory activity in transgenic zebrafish. Gene expression patterns in the catshark showed that there are some expression sites with high conservation of the expressed paralog(s) and other expression sites with events of paralog sub-functionalization during jawed vertebrate diversification, resulting in a wide variety of evolutionary scenarios within this gene family.

Conclusion

Dlx gene expression patterns in the catshark show that there has been little neo-functionalization in Dlx genes over gnathostome evolution. In most cases, one tandem duplication and two rounds of vertebrate genome duplication have led to at least six Dlx coding sequences with redundant expression patterns followed by some instances of paralog sub-functionalization. Regulatory constraints such as shared enhancers, and functional constraints including gene pleiotropy, may have contributed to the evolutionary inertia leading to high redundancy between gene expression patterns.

Randomized clinical trial of fluid restriction in colorectal surgery

BACKGROUND

Perioperative fluid therapy can influence postoperative hospital stay and complications after elective colorectal surgery. This trial was designed to examine whether an extremely restricted perioperative fluid protocol would reduce hospital stay beyond the existing fast-track hospital time of 7 days after surgery.

METHODS

Patients were randomized to restricted or standard perioperative intravenous fluid regimens in a single-centre trial. Randomization was stratified for colonic, rectal, open and laparoscopic surgery. Patients were all treated within a fast-track protocol (careful preoperative preparation, optimal analgesia, early oral nutrition and early mobilization). The primary endpoint was length of postoperative hospital stay. The secondary endpoint was complications within 30 days.

RESULTS

Seventy-nine patients were randomized to restricted and 82 to standard fluid therapy. Patients in the restricted group received a median of 3050 ml fluid on the day of surgery compared with 5775 ml in the standard group (P < 0·001). There was no difference between groups in primary hospital stay (median 6·0 days in both groups; P = 0·194) or stay including readmission (median 6·0 days in both groups; P = 0·158). The proportion of patients with complications was significantly lower in the restricted group (31 of 79 versus 47 of 82; P = 0·027). Vasopressors were more often required in the restricted group (97 versus 80 per cent; P < 0·001).

CONCLUSION

Restricted perioperative intravenous fluid administration does not reduce length of stay in a fast-track protocol.

Weekly chemotherapy with platinum as radio-sensitizer during concomitant chemoradiotherapy for squamous cell head and neck cancer

16541

Background: CRT protocols for locally advanced HNC commonly utilize single agent cisplatinum as the radiation- sensitizing chemotherpy. This is typically administered in q 3 weekly doses of 100 mg/sq m concomitantly with XRT. However, many pts are not candidates for this dose and schedule of cisplatinum delivery due to co-morbidities. Limited data are available regarding the efficacy of alternate dosing of platinum analogues.We therefore analysed our experience with alternate dosing of cisplatin or carboplatin administered concomitantly with XRT. Methods: IRB approval was obtained for this retrospective analysis. Tumor registry and pharmacy data were reviewed to identify eligible pts. between 2004–2006 who were treated with alternate dosing of platinum with XRT. Pt characteristics recorded included: age, gender, stage, site of disease, type of chemotherpeutic agent used carboplatin or cisplatinum, number of doses administered, local disease free survival and overall survival. Results: Eleven pts were identified. Median age: 64 years (44–75); Gender: M:F::8:3; Sites: Oral cavity: n=2; Pharynx: n=11; Stage III: n=3; Stage IVa &b: n=8. Cisplatin weekly (doses 30–40mg/sqm): n=8; Carboplatin weekly AUC=2: n=3; Cisplatin weekly, changed to carboplatin: n=1. Nine of 11 pts achieved a local CR (82%); one pt has achieved a near CR and one pt achieved a PR and required salvage laryngectomy. At a median follow up of 14 mos (range: 4–34), all pts remain alive. In addition to the pt that achieved a PR after initial treatment, one other pt has required surgical salvage at 23 mos post CRT. No treatment related mortality occurred in this series. Conclusions: Weekly administration of cisplatin and carboplatin appears to be a feasible alternative to standard dose and schedule of cisplatin with acceptable efficacy. Future studies should compare targetted therapies such as cetuximab with or in combination with weekly platinum regimens during CRT for pts not eligible for standard dose cisplatinum.

No significant financial relationships to disclose.

Late adverse effects of short-course preoperative radiotherapy in rectal cancer

Background

Preoperative radiotherapy improves local control and survival in rectal cancer, but there are few reports on long-term morbidity. The aims of this study were to compare long-term morbidity and quality of life in patients undergoing rectal cancer surgery with or without preoperative radiotherapy.

Methods

A total of 252 patients, randomized within the two Stockholm trials on preoperative radiotherapy in rectal cancer, were alive at a mean of 15 years after surgery. Some 139 of these patients were available for follow-up by questionnaires and clinical examination. Questionnaires regarding medical history and quality of life were completed by all patients. All patients had a clinical examination, and those without a stoma underwent rigid sigmoidoscopy.

Results

Overall, patients who had preoperative radiotherapy experienced significantly more late complications than those who did not (69 versus 43 per cent; P = 0·002). This morbidity consisted mainly of cardiovascular disease (35 versus 19 per cent; P = 0·032), faecal incontinence (12 of 21 versus 11 of 42 patients having anterior resection; P = 0·013) and urinary incontinence (45 versus 27 per cent; P = 0·023). No significant differences between groups were found for hip or pelvic fractures, small bowel obstruction or global quality of life.

Conclusion

Preoperative short-course, high-dose radiotherapy in patients with rectal cancer increases the risk of anal and urinary dysfunction, and may lead to increased cardiovascular morbidity, at long-term follow-up.

Value of positron emission tomography (PET) scan in treatment decision making for nodal metastases in head and neck squamous cell cancer

5577

Background: Management of neck disease in patients with Head and Neck Squamous cell cancer (HNC) who are initially treated with combined radiation and chemotherapy (CRT) remains controversial. Standard treatment options include neck dissection (ND) or close observation. More recently PET scans have been used to stage and monitor response to therapy in patients with HNC. We performed a retrospective analysis of patients diagnosed with HNC stages N2b or higher, treated with combined CRT, and who were monitored for disease response by PET scans. Our observations on the utility of PET scans in monitoring response to therapy and in determining the role of elective NDs in this setting are reported. Methods: A retrospective review of medical records of all patients diagnosed at our institution with HNC Stages TxN2b, N2c or N3 between the years 2002 and 2005 was undertaken. IRB approval was obtained for this study.To be eligible for this analysis, patients must have had baseline and follow up PET scans at the end of CRT and prior to ND. Data regarding age, gender, primary tumor site, stage, baseline and follow up PET scan results, operative pathology of ND when performed, and local control were recorded. Results: Fifteen patients were identified. Median age was 55 years (range 37–76). Male: Female ratio was 13:2. Primary site of tumor was Pharynx (Base of tongue: n = 3, tonsil: n = 11); Lip and oral cavity: n = 1. Stages: IVa : n = 12; IVb: n = 3. N stage: N2b: n = 12; N2c: n = 1; N3: n = 2. Post CRT, all patients were followed with serial clinical examinations, PET ± CT scans. 13 of 15 patients had negative PET activity in the neck at the completion of CRT and remain disease free in the neck at a median follow up of one year. Post treatment PET scans were positive at the primary site in 2 of 15 patients; and positive in the neck in 2 of 15 patients. These 4 patients underwent ND after completing CRT. Operative pathology was positive for nodal disease in 2 of 4 patients who had persistent mild or significant activity on PET scan either at the primary site or in the neck. Conclusions: Post CRT PET negativity in the neck and at the site of primary tumor is associated with continued disease free status in the neck and these patients may be managed conservatively without requiring a neck dissection.

No significant financial relationships to disclose.

Silicone-covered metal stents: an in vitro evaluation for biofilm formation and patency

Self-expanding metal stents are being used more commonly to prevent biliary tract obstruction. Silicone-covered self-expanding metal stents (Wallstent, Schneider, Inc.) have been developed to prevent tumor ingrowth. Biofilm formation and occlusion material in silicone-covered self-expanding metal stents compared to standard polyethylene stents were examined in an in vitro model. Matched pairs of polyethylene and silicone-covered metal stents were perfused with infected bile for 8, 12, and 16 weeks at a rate of 0.5 cc/min at 37 degrees C. Two reservoirs fitted with silicone-covered metal stents had ampicillin/sulbactam added and were perfused for 16 weeks. The stents were then analyzed by scanning electron microscopy and light microscopy for biofilm formation and presence of occlusion material. The two ampicillin/sulbactam-treated stents showed no biofilm formation. Biofilm was seen on all of the remaining stents. There was a difference in occlusion thickness between the 8- and 16-week polyethylene stents, and no difference between the biofilm thickness at 8, 12, or 16 weeks in the silicone-covered metal stents. Silicone-covered self-expanding metal stents will likely extend patency rates in malignant obstructive jaundice by providing a larger lumen for bile flow and allowing cyclical antibiotics to prevent bacterial biofilm formation.

Use of single percutaneous endoscopic gastrostomy in management of gastric volvulus in three patients

Gastric volvulus is a rare condition that occurs when the stomach twists either in an organoaxial or mesenteroaxial direction. In patients with recurrent episodes of volvulus, standard therapy is surgical correction. Many patients, however, are not candidates for surgical therapy because of comorbid conditions or advanced age. Our aim was to determine if the insertion of a single percutaneous gastrostomy tube placement would assist in management of gastric volvulus in patients not able to undergo surgical therapy. The alpha-loop maneuver was used to reduce gastric volvulus in three elderly patients. A percutaneous endoscopic gastrostomy tube was then inserted to prevent recurrent volvulus. Single percutaneous gastrostomy tube placement was successful in managing volvulus in these three patients. Single percutaneous endoscopic gastrostomy tube placement is a useful treatment alternative to surgery in patients requiring therapy of gastric volvulus.

Comparison of RapID yeast plus system with API 20C system for identification of common, new, and emerging yeast pathogens

The ability to identify yeast isolates by the new enzymatic RapID Yeast Plus System was compared to the ability to identify yeast isolates by the API 20C system. A total of 447 yeast isolates representing Blastoschizomyces capitatus, 17 Candida spp., 5 Cryptococcus spp., Geotrichum spp., 2 Hanseniaspora spp., Hansenula anomala, Hansenula wingei, 3 Rhodotorula spp., Saccharomyces cerevisiae, Sporobolomyces salmonicolor, Trichosporon beigelii, and 2 Prototheca spp. were evaluated. Also, five quality control strains (Candida spp. and Cryptococcus laurentii) with well-documented reactivities by the RapID Yeast Plus System were used. Each isolate was evaluated by both methods with a 48-h culture grown at 30 degrees C on Sabouraud dextrose agar (Emmons modification) by following the recommendations of the manufacturers. The RapID Yeast Plus System enzymatic reactions were read after 4 h of incubation, and the API 20C carbohydrate assimilation identification profiles were obtained after 72 h of incubation. There was good (95.7%) agreement between the identifications obtained by the two methods with the eight common Candida spp. and with Cryptococcus neoformans. The agreement was lower when the emerging Candida spp. and other yeast-like pathogens were tested (79.1 and 75.2%, respectively). These preliminary data suggest the potential utility of the RapID Yeast Plus System for use in the clinical laboratory for the rapid identification of common yeast pathogens as well as certain new and emerging species.

Evolutionary body building: adaptive physical designs for robots

Creating artificial life forms through evolutionary robotics faces a "chicken and egg" problem: Learning to control a complex body is dominated by problems specific to its sensors and effectors, while building a body that is controllable assumes the pre-existence of a brain. The idea of coevolution of bodies and brains is becoming popular, but little work has been done in evolution of physical structure because of the lack of a general framework for doing it. Evolution of creatures in simulation has usually resulted in virtual entities that are not buildable, while embodied evolution in actual robotics is constrained by the slow pace of real time. The work we present takes a step in addressing the problem of body evolution by applying evolutionary techniques to the design of structures assembled out of elementary components that stick together. Evolution takes place in a simulator that computes forces and stresses and predicts stability of three-dimensional brick structures. The final printout of our program is a schematic assembly, which is then built physically. We demonstrate the functionality of this approach to robot body building with many evolved artifacts.

Inhibition of biliary endoprostheses occlusion by ampicillin-sulbactam in an in vitro model

An important first step in stent occlusion is the formation of a bacterial biofilm. This is followed by deposition of granules similar to that found in brown pigment stones. Previous in vitro models for studying occlusion have used synthetic biles without bilirubin or pooled human bile, which is limited in supply. Our aim was to develop a new in vitro model of stent occlusion with porcine gallbladder bile and then, with the model, assess whether ampicillin-sulbactam can prevent biofilm formation and thus occlusion. Sterile porcine gallbladder bile was contaminated with Escherichia coli then divided into eight reservoirs, four of which then received ampicillin-sulbactam. The bile was then circulated through 10F polyethylene stents. Bile was changed weekly for 8 weeks. In the stents that were untreated, biofilm and sludge were seen in all four, whereas the four ampicillin-sulbactam-treated stents had no biofilm when viewed by electron microscopy. Furthermore, the levels of calcium, cholesterol, and bilirubin in the reservoirs decreased significantly in the untreated bile as compared with the treated bile (p < 0.05). In this in vitro model, the losses of calcium, cholesterol, and bilirubin are likely caused by deposition of granules into the biofilm matrix. Ampicillin-sulbactam can prevent biofilm formation if used continuously.

Use of oral GoLytely solution in relief of refractory fecal impaction

Constipation and fecal impaction are common disorders with multiple treatment options. We describe the use of GoLytely oral solution in 10 patients admitted to a community hospital and referred to a single gastroenterologist for fecal impaction refractory to conventional medical treatment. Seven women and three men received enemas, bisacodyl suppositories, and digital fragmentation either solely or in combination prior to the administration of GoLytely oral solution. The patients had no clinical and radiological evidence of bowel obstruction. All had underlying cardiovascular problems. Their mean age was 78.1 years (range 49-100 years). GoLytely oral solution (Braintree Laboratories, Inc.) was administered at a rate of 100 ml/hr per orem to three patients, via nasogastric tube in six patients, and via gastrostomy tube in one patient. All 10 patients were able to regularly pass feces and show radiographical colorectal clearing within 6.0 to 57.25 hr (mean 23.60 hr). No significant complications were observed. Eight patients were discharged from the hospital within 24 hr of termination of treatment while two patients remained for unrelated medical conditions. GoLytely oral solution effectively relieved fecal impaction in 10 patients refractory to conventional medical treatment.

Volvulus of the small bowel: an uncommon complication after laparoscopic cholecystectomy

We report here two patients with volvulus of the small bowel after laparoscopic cholecystectomy (LC). There has been only one case report of a similar condition after LC in the English literature; the patient had malrotation of the midgut. Both patients we are reporting had previous pelvic surgery resulting in intraabdominal adhesions. Volvulus had occurred along an axis between the mesenteric attachment and the adhesion to the parietal peritoneum of the involved loop of small bowel. The creation of pneumoperitoneum could conceivably allow rotation to occur. One patient presented with signs of peritonitis from a gangrenous segment of small bowel. The other presented with continued abdominal pain after surgery. Definitive diagnosis was made only at laparotomy. Previous surgery is considered a relative contraindication to LC, although the incidence of morbidity and conversion to open procedure appear not to be influenced by previous surgery. Surgeons should be aware of volvulus as a complication after LC in patients who had previous abdominal surgery.

Erythrocyte thiolmethyltransferase: another failed marker for Alzheimer's and Parkinson's diseases

There are reports that patients with Parkinson's disease (PD) and Alzheimer's disease (AD) have reduced levels of thiolmethyltransferase (TMT) in erythrocyte membranes. TMT methylates thiols and thiocarbamates, thereby reducing their toxicity. We examined TMT levels in erythrocytes from patients with PD and AD and from age-matched controls. Specific activities of TMT were 564 +/- 199 U/mg protein in PD (n = 32), 513 +/- 118 in AD (n = 13), and 565 +/- 183 in controls (n = 35). There was no difference between any of the groups (p = 0.64). We failed to confirm TMT as a marker for neurodegenerative diseases or for this metabolic defect predisposing to susceptibility to neurotoxins.

Percutaneous hepatic vein isolation and high-dose hepatic arterial infusion chemotherapy for unresectable liver tumors

PURPOSE

This prospective, nonrandomized trial evaluated a percutaneous isolated chemotherapy perfusion approach for treating advanced primary and metastatic liver tumors. Chemotherapy was administered via hepatic artery catheter and hepatic venous blood isolated by a novel percutaneous double-balloon inferior vena cava (IVC) catheter was passed through a detoxification/filtration cartridge in a venovenous bypass circuit.

PATIENTS AND METHODS

Among 23 patients enrolled onto the study, 58 procedures were performed on 21 patients. Twelve patients received dose escalations of fluorouracil (5-FU) (1,000 mg/m2 to 5,000 mg/m2), and nine received dose escalations of doxorubicin (50 mg/m2 to 120 mg/m2). Pharmacokinetic studies included drug accumulation in the liver, extraction by detoxification filters, systemic exposure, and alterations of half-life. Each patient received two treatments at 3-week intervals. Those showing stabilization or response received additional treatments.

RESULTS

There was a direct relationship between dose and peak concentration of drug entering the hepatic veins. The system functioned efficiently throughout the dose range, with extraction efficiencies ranging from 64% to 91% (P < .001). The hepatic vein drug levels showed a sixfold increase in 5-FU with dose escalation from 1,000 to 5,000 mg/m2, and a twofold increase in dox with dose escalation from 50 to 120 mg/m2 (P < .001, filter-mediated drug extraction). The treatments were accomplished with only an overnight hospital stay and no mortality. The common procedure-related toxicity was transient hypotension (grade I to II), due to catecholamine depletion by the filter. Dose-limiting toxicity (leukopenia) was observed in patients receiving 5-FU at a dose of 5,000 mg/m2 and doxorubicin at a dose of 120 mg/m2. Significant tumor response (> 95% reduction) was obtained in two patients receiving doxorubicin at 90 mg/m2 and 120 mg/m2.

CONCLUSION

The use of a double-balloon catheter to isolate and detoxify hepatic venous blood during intraarterial therapy is technically feasible, safe, and allows administration of large doses of intrahepatic chemotherapy at short intervals. This approach should allow new dose-intensification strategies to increase tumor responses in primary and metastatic liver tumors.

Mongolian gerbils (Meriones unguiculatus) absorb beta-carotene intact from a test meal

Because a yellow color has been observed in the fat pads of Mongolian gerbils fed a nonpurified diet, we designed the current study to determine whether adult male gerbils would absorb beta-carotene intact from a test meal. Thirty-five gerbils (80-90 g) were adapted to the laboratory and fed a standard purified diet free of beta-carotene for 16-19 d. Gerbils were then fed a test meal consisting of 279 nmol of beta-carotene as 10% water-soluble beadlets suspended in 0.5 mL of Ensure. Gerbils (n = 5) were killed at 0, 2, 4, 6, 12, 24 or 72 h after the test meal, blood was obtained by cardiac puncture, and tissues were taken for beta-carotene analysis. No beta-carotene was detected in serum at 0 or 72 h, whereas beta-carotene was present at all other sampling times. Serum beta-carotene peaked at 4 h, at a level of 88 nmol/L. beta-Carotene was detected in the liver of all groups; however, the concentration increased from -34 pmol/g to a maximum concentration of 926 pmol/g at 24 h after the test meal. Other tissues also contained beta-carotene. The results demonstrate that Mongolian gerbils, like ferrets and preruminant calves, absorb beta-carotene intact when beta-carotene is provided at a physiological level in a test meal. This species may be particularly useful for evaluation of the role of antioxidants, such as beta-carotene, in LDL oxidation.

Short-term psychotherapy of personality disorders

OBJECTIVE

The efficacy of short-term psychotherapy has become an area of increasing interest. The primary objective of this study was to assess the results of two forms of short-term psychotherapy in patients with personality disorders.

METHOD

Eighty-one patients with personality disorders were randomly assigned to brief adaptive psychotherapy, short-term dynamic psychotherapy, or a waiting list for therapy. Outcome at termination of therapy for the treatment groups and at the end of the waiting period for the waiting list group was evaluated by means of ratings of target complaints and scores on the SCL-90 and the Social Adjustment Scale. In addition, for 38 of the treated patients, target complaints were reevaluated an average of 1.5 years after treatment ended.

RESULTS

Patients in the two therapy conditions improved significantly on all measures in comparison with the patients on the waiting list. There was no significant difference between the results in the two therapy conditions. The waiting list period averaged approximately 15 weeks; treatment averaged 40 weeks. At follow-up, after an average of 1.5 years, target complaint ratings were not significantly different from those at the termination of therapy.

CONCLUSIONS

These data indicate that brief adaptive psychotherapy and short-term dynamic psychotherapy are effective for patients with certain types of personality disorder and that the two therapy approaches do not differ in overall outcome.

"PCL" a new automatic fast reader suitable for in vivo dosimetry

The authors present a new automatic TLD reader specially designed for medical dosimetric applications, which allow considerable time-saving. The "PCL" reader is based on an isothermal heating kinetics and can be used with TL material of any nature and any shape (powder, microrods, pellets). Doses from 1 microGy to 10 Gy can be measured, or higher doses by interposing an optical absorber in front of the PM. The readout system is controlled by an IBM compatible personal computer. Results can be printed under the form defined by the users and then can be straightly stored in a patient sheet or an experience book. Tests performed with LiF chips TLD 100 and 700 (HARSHAW), Li2B4O7:Mn discs LiB (ALNOR), LiF powder PTL 717 (DESMARQUET) and Li2B4O7:Cu powder (CEN-FAR) are presented. They show a good reproducibility and interesting dosimetric properties.

Ventilatory threshold and maximal oxygen uptake during cycling and running in female triathletes

Maximal oxygen uptake (VO2max) and the ventilatory threshold (Tvent) were measured during cycle ergometry (CE) and treadmill running (TR) in a group of 10 highly trained female triathletes. Tvent was defined as the VO2 at which the ventilatory equivalent for oxygen increased without a marked rise in the ventilatory equivalent for carbon dioxide. Female triathletes achieved a significantly higher mean (+/- SE) relative VO2max for running (63.6 +/- 1.2 ml.kg-1.min-1) than for cycling (59.9 +/- 1.3 ml.kg-1.min-1). When oxygen uptake measured at the ventilatory threshold was expressed as a percent of VO2max, the mean value obtained for TR (74.0 +/- 2.0% of VO2max) was significantly greater than the value obtained for CE (62.7 +/- 2.1% of VO2max). This occurred even though the total training time and intensity were similar for the two modes of exercise. Female triathletes had average running and cycling VO2max values that compared favorably with maximal oxygen uptake values previously reported for elite female runners and cyclists, respectively. However, mean running and cycling Tvent values (VO2 Tvent as%VO2max) were lower than recently reported values for single-sport athletes. The physiological variability between the triathletes studied and single-sport athletes may be attributed in part to differences in training distance or intensity, and/or to variations in the number of years of intense training in a specific mode of exercise. It was concluded that these triathletes were well-trained in both running and cycling, but not to the same extent as female athletes who only train and compete in running or cycling.

Brief psychotherapy of personality disorders

Thirty-two patients with personality disorder diagnoses were randomly assigned to two treatment conditions that vary on several techniques of brief dynamic psychotherapy. Seventeen patients constituted a waiting list control group. The two brief psychotherapies showed significant improvement on target complaints, SCL-90, and Social Adjustment Scale-SR compared with the control subjects. The two therapy groups were similar in overall outcome but showed interesting differences on several subscale measures. Process measurements of videotaped sessions revealed significant variations in frequencies of therapist interventions across the two treatment conditions, which validated planned differences in the treatment techniques.

Change in patient affect/defense ratio from early to late sessions in brief psychotherapy

The current study examined changes in the ratio of patients' affective and defensive behaviors during the course of brief psychodynamic psychotherapy. Treatments of 16 patients were videotaped. For each patient, four sessions were evaluated with a minute-by-minute coding system of process variables. When patients were grouped according to outcome scores, significant differences between the high outcome and the average-to-low outcome groups emerged. During the early phase of treatment, patients in both groups showed an average of one affective response per five defensive responses. By the late phase of treatment, the high outcome patients showed a marked shift to one affective response per two defensive responses, while the low outcome patients remained the same. An incidental finding was a negative correlation between good outcome and the ratio of defensive behavior to total patient activity.

Derivation of midinfrared (5-25 micrometers) optical constants of some silicates and palagonite

The midinfrared 2000-400 cm-1 (5-25 micrometers) optical constants (real (n) and imaginary (k) indices of refraction) are presented for: (1) pyrophyllite; (2) kaolinite; (3) serpentine; (4) montmorillonite; (5) saponite; (6) palagonite; and (7) orthopyroxene. Comparison of the values derived here with those previously presented for serpentine, montmorillonite, and palagonite is generally quite good and discrepancies between values are probably due to either chemical differences between the actual samples or different techniques used to derive the values. For montmorillonite, saponite, and palagonite we were able to derive optical constants in the region of the H2O-bending fundamental near 6 micrometers. We find that if a pellet of pure material can be produced with a mirror-like surface then the optical constants of clays and other noncohesive materials can be readily derived.

Heat shock response of murine Chlamydia trachomatis

We have investigated the heat shock response in the mouse pneumonitis strain of Chlamydia trachomatis. The kinetics of the chlamydial heat shock response resembled that of other procaryotes: the induction was rapid, occurring over a 5- to 10-min time period, and was regulated at the level of transcription. Immunoblot analysis and immunoprecipitations with heterologous antisera to the heat shock proteins DnaK and GroEL demonstrated that the rate of synthesis, but not the absolute amount of these two proteins, increased after heat shock. Using a general screen for genes whose mRNAs are induced by heat shock, we identified and cloned two of these. DNA sequence analysis demonstrated that one of the genes is a homolog of dnaK. Further sequence analysis of the region upstream of the dnaK gene revealed that the chlamydial homolog of the grpE gene is located just adjacent to the dnaK gene. The second locus encoded three potential nonoverlapping open reading frames. One of the open reading frames was 52% homologous to the ribosomal protein S18 of Escherichia coli and thus presumably encodes the chlamydial homolog. Interestingly, this ribosomal protein is not known to be induced by heat shock in E. coli. S1 nuclease and primer extension analyses located the start site of the dnaK transcript to the last nucleotide of the grpE coding sequence, suggesting that these two genes, although tandemly arranged, are transcribed separately. No promoter sequences resembling the E. coli consensus heat shock promoter could be identified upstream of either the C. trachomatis dnaK, grpE, or S18 gene. The induction of the dnaK and S18 mRNAs by heat shock occurred at a transcriptional level; their induction could be blocked by rifampin. The mechanisms of induction for these two loci were not the same, however; they were differentially sensitive to chloramphenicol. Whereas the induction of dnaK mRNA required de novo protein synthesis, the induction of the S18 mRNA did not. Thus, C. trachomatis utilizes at least two different pathways to induce the transcription of mRNAs encoding proteins induced in the heat shock response.

Cloning and characterization of RNA polymerase core subunits of Chlamydia trachomatis by using the polymerase chain reaction

Taking advantage of sequence conservation of portions of the alpha, beta, and beta' subunits of RNA polymerase of bacteria and plant chloroplasts, we have designed degenerate oligonucleotides corresponding to these domains and used these synthetic DNA sequences as primers in a polymerase chain reaction to amplify DNA sequences from the chlamydial genome. The polymerase chain reaction products were used as a probe to recover the genomic fragments encoding the beta subunit and the 5' portion of the beta' subunit from a library of cloned murine Chlamydia trachomatis DNA. Similar attempts to recover the alpha subunit were unsuccessful. Sequence analysis demonstrated that the beta subunit of RNA polymerase was located between genes encoding the L7/L12 ribosomal protein and the beta' subunit of RNA polymerase; this organization is reminiscent of the rpoBC operon of Escherichia coli. The C. trachomatis beta subunit overproduced in E. coli was used as an antigen in rabbits to make a polyclonal antibody to this subunit. Although this polyclonal antibody specifically immunoprecipitated the beta subunit from Chlamydia-infected cells, it did not immunoprecipitate core or holoenzyme. Immunoblots with this antibody demonstrated that the beta subunit appeared early in infection.

Change in patient affect/defense ratio from early to late sessions in brief psychotherapy

The current study examined changes in the ratio of patients' affective and defensive behaviors during the course of brief psychodynamic psychotherapy. Treatments of 16 patients were videotaped. For each patient, four sessions were evaluated with a minute-by-minute coding system of process variables. When patients were grouped according to outcome scores, significant differences between the high outcome and the average-to-low outcome groups emerged. During the early phase of treatment, patients in both groups showed an average of one affective response per five defensive responses. By the late phase of treatment, the high outcome patients showed a marked shift to one affective response per two defensive responses, while the low outcome patients remained the same. An incidental finding was a negative correlation between good outcome and the ratio of defensive behavior to total patient activity.

Identification of calcium-calmodulin multifunctional protein kinase II in rabbit kidney

Recent studies have demonstrated that calcium/calmodulin-dependent multifunctional protein kinase II (CaM-KII) inhibits the reconstituted Na(+)-H+ exchanger from the brush border membrane of proximal convoluted tubule of the rabbit kidney. The present studies were undertaken to evaluate the physiological relevance of this finding by establishing the presence of CaM-KII in rabbit kidney and proximal convoluted tubule cells by Northern RNA hybridization analysis to demonstrate the messenger RNA (mRNA) for CaM-KII and by a selective enzymatic assay of CaM-KII using a synthetic peptide substrate. A single 4.9 Kb mRNA was observed on hybridization of total RNA from rabbit kidney cortex and medulla and from an enriched suspension of rabbit kidney proximal convoluted tubules with a cDNA for rat brain CaM-KII. An enzyme assay using a synthetic peptide substrate representing the site phosphorylated by CaM-KII on glycogen synthase demonstrated calcium-calmodulin dependent protein kinase activity in both rabbit kidney cortex (specific activity of 662 +/- 127 nmol.min-1.mg protein-1) and proximal tubule cells (546 +/- 77 nmol.min-1.mg protein-1). These data establish the presence of CaM-KII in the rabbit kidney, and suggest a role for this enzyme in the control of renal electrolyte transport.

Ventilatory threshold and maximal oxygen uptake during cycling and running in triathletes

VO2max and the ventilatory threshold (Tvent) were measured during cycle ergometry (CE) and treadmill running (TR) in a group of 10 highly trained male triathletes. Tvent was indicated as the VO2 at which the ventilatory equivalent for oxygen increased without a marked rise in the ventilatory equivalent for carbon dioxide. Triathletes achieved a significantly higher VO2max for TR (75.4 +/- 7.3 ml.kg-1.min-1) than for CE (70.3 +/- 6.0 ml.kg-1.min-1). Mean CE VO2max was 93.2% of the TR value. Average VO2max values for CE and TR compared favorably with values reported for elite single-sport athletes and were greater than those previously reported for other male triathletes. CE Tvent occurred at 3.37 +/- 0.32 l.min-1 or 66.8 +/- 3.7% of CE VO2max, while TR Tvent was detected at 3.87 +/- 0.33 l.min-1 or 71.9 +/- 6.6% of TR VO2max. The VO2 (l.min-1) at which Tvent occurred for TR was significantly higher than for CE (P less than 0.001). Although the VO2 values at TR Tvent expressed as a percentage of VO2max were consistently higher than for CE, the difference between the means did not reach statistical significance (P greater than 0.05). The average Tvent for CE (as %VO2max) was nearly identical to Tvent values reported in the literature for competitive male cyclists, whereas TR Tvent was lower than recently reported values for elite distance runners and marathoners. We speculate that triathlon training results in general (cross-training) adaptations which enhance maximal oxygen uptake values, whereas anaerobic threshold adaptations occur primarily in the specific muscle groups utilized in training.

The time limit in brief psychotherapy

The time limit in psychoanalytically oriented brief psychotherapy has been construed as a motivation for the patient and the therapist to work more efficiently in therapy and as a stimulation of the patient's unconscious conflicts relating to separation and loss. The authors show that the time limit, in addition to the above functions, affects all focal conflicts in brief psychotherapy, whether or not they relate to separation issues. The time limit helps both patient and therapist to examine aspects of the patient's focal conflicts that tend to perpetuate symptoms or maladaptive patterns of behavior--that is, the primary gain of the symptom--and may therefore play a crucial role in the efficacy of brief psychotherapy. The authors also discuss implications for technique.

The sex-determining region of the human Y chromosome encodes a finger protein

The presence or absence of the Y chromosome determines whether a mammalian embryo develops as a male or female. In humans, genetic deletion analysis of "sex-reversed" individuals has identified a small portion of the Y chromosome necessary and sufficient to induce testicular differentiation of the bipotential gonad. We report the cloning of a 230-kilobase segment of the human Y chromosome that contains some or all of the testis-determining factor gene (TDF), the master sex-determining locus. The cloned region spans the deletion in a female who carries all but 160 kilobases of the Y. Certain DNA sequences within this region were highly conserved during evolution; homologs occur on the Y chromosomes of all mammals examined. In particular, homologous sequences are found within the sex-determining region of the mouse Y chromosome. The nucleotide sequence of this conserved DNA on the human Y chromosome suggests that it encodes a protein with multiple "finger" domains, as first described in frog transcription factor IIIA. The encoded protein probably binds to nucleic acids in a sequence-specific manner, and may regulate transcription. Very similar DNA sequences occur on the X chromosome of humans and other mammals. We discuss the possibility that the Y-encoded finger protein is the testis-determining factor, and propose models of sex determination accommodating the finding of a related locus on the X chromosome. The presence of similar sequences in birds suggests a possible role not only in the XX/XY sex determination system of mammals, but also in the ZZ/ZW system of birds.

Spontaneous bilateral pneumothorax in an infant with bronchiolitis

Spontaneous pneumothorax is an uncommon complication of bronchiolitis due to respiratory syncytial virus. Bilateral spontaneous pneumothorax in an infant with respiratory syncytial virus bronchiolitis has not been previously reported. We report the case of a four-month-old infant who presented in respiratory distress owing to respiratory syncytial virus bronchiolitis with bilateral pneumothoraces. The infant improved with evacuation of air from the chest.

Long-term endocrine sequelae after treatment of medulloblastoma: prospective study of growth and thyroid function

Endocrine evaluations were performed prospectively in 22 patients with medulloblastoma (ages 2 1/2 to 23 1/2 years at diagnosis), after craniospinal radiation with or without adjuvant chemotherapy. The mean craniospinal hypothalamic-pituitary). and thyroid radiation doses were 3600 and 2400 rads, respectively. Fourteen (73%) of 19 patients who had not yet completed their growth experienced a decrease in growth velocity. However, only three of 10 of these children, who underwent growth hormone stimulation tests, had evidence of deficient growth hormone responses, suggesting that growth hormone secretory or regulatory dysfunction, rather than absolute growth hormone deficiency, is present in the majority of these children. Elevated thyroid-stimulating hormone levels were noted in 15 of 22 patients; one patient had hypothalamic hypothyroidism. Thus, the late effects of therapy for medulloblastoma include frequent endocrine morbidity involving hypothalamic-pituitary and thyroid dysfunction.

Combined effects of alcohol and lithium on body composition in the rat model

Alcohol markedly enhances Li+ retention in blood and muscle in rats taking Li and alcohol. The marked enlargement of the exchangeable Na+ space which occurs with alcohol alone, Li+ alone, and to an even greater extent with combined therapy, results from extensive mobilization of "bound" bone sodium, which is transferred to intracellular sites, demonstrably in skeletal muscle, and presumably in other cells. This 87% increase in measured intracellular Na+, and concomitant decrease in K+, would be predicted to produce profound effects on the intracellular ionic milieu, and on membrane function. Lithium is associated with a decrease in food and fluid intake, and this effect is enhanced by alcohol. However the decrease in intake did not result in nutritionally significant deficits in either group, and therefore the observed abnormalities in body composition did not result from caloric, protein, K, Na, or Ca deficiency.

Lymphosarcoma of the duodenum associated with carcinoma of the lung. Five-year survival

The case presented describes a patient with lymphosarcoma of the duodenum associated with carcinoma of the lung. This emphasizes the basic problems which lymphosarcoma of the duodenum presents. They are vague symptoms until late in the course of the disease, the absence of early physical findings, the difficulty in interpretation of radiological studies and the frequent association with other primary malignancies elsewhere.