Phylo-geographic analysis of whitefly on the basis of mitochondrial cytochrome oxidase 1 gene

Abstract Bemisia tabaci is a species complex that causes damage to its broad range of plant hosts through serious feeding. It transmits plant viruses of different groups to important agricultural crops. Some important cash crops of Pakistan are sugar cane, rice, tobacco and seed oil. It shows high genetic variability and is differentiated as races or biotypes. Biotypes are, biotype Q, biotype B, biotype B2, biotype M, biotype L, biotype A, biotype H, biotype C, biotype K, biotype N, biotype R, biotype E, biotype P, biotype J, biotype S, biotype AN. Although the current report based on the Bayesian study of mitochondrial cytohrome oxidase gene1 (CO1) DNA sequences has classified the different populations of whiteflies into twelve genetic groups which are Mediterranean, Sub-Saharan Africa silverleafing, Indian Ocean, Asia II, Asia I, Australia, New World, Italy, China, Sub-Saharan Africa non-silverleafing, Mediterranean/Asia Minor/Africa and Uganda sweet potato. Begomoviruses is largest group of viruses transmitted by B. tabaci and cause major diseases of crops such as tomato and chili leaf curl disease, cassava mosaic disease; yellow mosaic disease of legumes and cotton leaf curl disease. The main objective of current study is to inculpate knowledge regarding genetic diversity of whitefly in cotton fields across Pakistan via analysis of partial DNA sequence of mitochondrial gene Cytochrom Oxidase I (mtCO1).

Screening, biochemical characterization and antibiotics resistance/susceptibility of bacteria isolated from native soil and water samples

Abstract The present study was conducted to isolate and characterize bacteria from water and soil sample taken from the Lahore Canal at different sites i.e. Mall Road, Mohlanwal and Khera site. Isolated bacterial strains were identified on the basis of morphological and biochemical tests. Identification was confirmed by culturing bacteria on selective media. Antibiotic resistance test was also performed to observe the resistance of bacteria against different antibiotics. Blood agar test was performed for identification of different pathogenic bacteria. The result revealed that water and soil samples of Lahore Canal Lahore from different sites were contaminated with Escherichia coli, Salmonella sp., Vibrio sp., Bacillus spp., Enterococcus sp. and Staphylococcus spp. Due to presence of these pathogens, this water is not suitable for any domestic and irrigation use. Study also revealed that water of the Lahore Canal is harmful for human health as it is contaminated with bacteria that can cause severe disease e.g., Escherichia coli can cause gastroenteritis, Bacillus spp. can cause nausea and vomiting, Enterococcus may infect urinary tract, Salmonella sp. is responsible for Bacteremia, Staphylococcus spp. can cause mild fever and Vibrio sp. can be the reason of cholera. Thus it is rendered unfit for any kind of human use even other than drinking like swimming, bathing, washing etc., until and unless some remedial measures are employed to eradicate pathogenic microorganisms by WASA and LWMS according to standards of WHO. Similarly, it is quite harmful, when and where ever it is used for irrigation without proper treatment.

Antibacterial activity of Ricinus communis plant extract against antibiotic resistant Helicobacter pylori and Gluconobacter oxydans isolated from fresh apple juices samples

Bacteria were isolated from samples of Fresh Apple juices from shops of three different localities of Lahore. Analysis of samples from Liberty, Anarkali and Yateem khana Markets show different levels of contamination. There were pathogenic and non-pathogenic bacteria in all samples and were identified by the morphological and biochemical tests. Most of the plasmids of pathogenic bacteria were 4kb in their molecular size. Ribotyping of 16S ribosomal RNA gene sequencing was done to confirm Helicobacter pylori strain and Gluconobacter oxydans. The highest sensitivity of 210mm was shown by Enterobacter sp. against Aztheromysine disk (15µg) while Micrococcus sp. was highly resistant against all of the Antibiotics applied. The antibiotic resistance of pathogenic bacteria was also checked against Ricinus communis plant's extracts, all isolated bacterial pathogens were resistant but only, E.coli was inhibited at 300µl of the extracts. Presence of pathogenic bacteria in Apple juice samples was due to contamination of sewage water in drinking water while some of these pathogenic bacteria came from Apple's tree and other from store houses of fruits.

Significant production of vanillin and in vitro amplification of ech gene in local bacterial isolates

Vanillin is the major component which is responsible for flavor and aroma of vanilla extract and is produced by 3 ways: natural extraction from vanilla plant, chemical synthesis and from microbial transformation. Current research was aimed to study bacterial production of vanillin from native natural sources including sewage and soil from industrial areas. The main objective was vanillin bio-production by isolating bacteria from these native sources. Also to adapt methodologies to improve vanillin production by optimized fermentation media and growth conditions. 47 soil and 13 sewage samples were collected from different industrial regions of Lahore, Gujranwala, Faisalabad and Kasur. 67.7% bacterial isolates produced vanillin and 32.3% were non-producers. From these 279 producers, 4 bacterial isolates selected as significant producers were; A3, A4, A7 and A10. These isolates were identified by ribotyping as A3 Pseudomonas fluorescence (KF408302), A4 Enterococcus faecium (KT356807), A7 Alcaligenes faecalis (MW422815) and A10 Bacillus subtilis (KT962919). Vanillin producers were further tested for improved production of vanillin and were grown in different fermentation media under optimized growth conditions for enhanced production of vanillin. The fermentation media (FM) were; clove oil based, rice bran waste (residues oil) based, wheat bran based and modified isoeugenol based. In FM5, FM21, FM22, FM23, FM24, FM30, FM31, FM32, FM34, FM35, FM36, and FM37, the selected 4 bacterial strains produced significant amounts of vanillin. A10 B. subtilis produced maximum amount of vanillin. This strain produced 17.3 g/L vanillin in FM36. Cost of this fermentation medium 36 was 131.5 rupees/L. This fermentation medium was modified isoeugenol based medium with 1% of isoeugenol and 2.5 g/L soybean meal. ech gene was amplified in A3 P. fluorescence using ech specific primers. As vanillin use as flavor has increased tremendously, the bioproduction of vanillin must be focused.

Antibacterial and bacteriostatic potential of coelomic fluid and body paste of Pheretima posthuma (Vaillant, 1868) (Clitellata, Megascolecidae) against ampicillin resistant clinical bacterial isolates

Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.

Gut dysbiosis, inflammation and type 2 diabetes in mice using synthetic gut microbiota from diabetic humans

The study was aimed to assess impact of high fat diet (HFD) and synthetic human gut microbiota (GM) combined with HFD and chow diet (CD) in inducing type-2 diabetes (T2D) using mice model. To our knowledge, this is the first study using selected human GM transplantation via culture based method coupled dietary modulation in mice for in vivo establishment of inflammation leading to T2D and gut dysbiosis. Twenty bacteria (T2D1-T2D20) from stool samples of confirmed T2D subjects were found to be morphologically different and subjected to purification on different media both aerobically and anerobically, which revealed seven bacteria more common among 20 isolates on the basis of biochemical characterization. On the basis of 16S rRNA gene sequencing, these seven isolates were identified as Bacteroides stercoris (MT152636), Lactobacillus acidophilus (MT152637), Lactobacillus salivarius (MT152638), Ruminococcus bromii (MT152639), Klebsiella aerogenes (MT152640), Bacteroides fragilis (MT152909), Clostridium botulinum (MT152910). The seven isolates were subsequently used as synthetic gut microbiome (GM) for their role in inducing T2D in mice. Inbred strains of albino mice were divided into four groups and were fed with CD, HFD, GM+HFD and GM+CD. Mice receiving HFD and GM+modified diet (CD/HFD) showed highly significant (P<0.05) increase in weight and blood glucose concentration as well as elevated level of inflammatory cytokines (TNF-α, IL-6, and MCP-1) compared to mice receiving CD only. The 16S rRNA gene sequencing of 11 fecal bacteria obtained from three randomly selected animals from each group revealed gut dysbiosis in animals receiving GM. Bacterial strains including Bacteroides gallinarum (MT152630), Ruminococcus bromii (MT152631), Lactobacillus acidophilus (MT152632), Parabacteroides gordonii (MT152633), Prevotella copri (MT152634) and Lactobacillus gasseri (MT152635) were isolated from mice treated with GM+modified diet (HFD/CD) compared to strains Akkermansia muciniphila (MT152625), Bacteriodes sp. (MT152626), Bacteroides faecis (MT152627), Bacteroides vulgatus (MT152628), Lactobacillus plantarum (MT152629) which were isolated from mice receiving CD/HFD. In conclusion, these findings suggest that constitution of GM and diet plays significant role in inflammation leading to onset or/and possibly progression of T2D. .

Modulating the production of xylanase by Bacillus pumilus BS131 through optimization using waste fiber sludge

In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.

Pseudomonas aeruginosa associated pulmonary infections and in vitro amplification virulent rhamnolipid (rhlR) gene

BACKGROUND

Pseudomonas aeruginosa is a common opportunistic pathogenic bacterium with the ability to develop a strong communication pathway by quorum sensing system and different virulent factors. Among the various important secretions of P. aeruginosa rhamnolipid is important biological detergent, believed to be involved in the development of the biofilm and intercellular communication. It readily dissolves the lung surfactants that are then easily catalyzed by the phospholipases and in this way is involved in the acute pulmonary infection.

OBJECTIVE

research work was designed to investigate virulence and gene associated with virulence in P. aeruginosa responsible for pulmonary infections.

METHODS

In current study polymerase chain reaction (PCR) was used for the detection of the rhlR (rhamnolipid encoding) gene of isolated strains. A number of assays were performed that ensured its virulent behavior. Disc diffusion method was used to check its antibiotic resistance. Isolated strains were resistant to a number of antibiotics applied.

RESULT

It was found that males are more prone to respiratory infections as compared to females. Male members with age of 44-58 and 59-73 are at a higher risk, while females with age of 44-58 are also at a risk of pulmonary infections. Antibiotic resistance was observed by measuring zone of inhibition in strains GCU-SG-M4, GCU-SG-M3, GCU-SG-M5, GCU-SG-M2, GCU-SG-M1 and GCU-SG-M6. GCU-SG-M2 was resistant to fluconazole (FLU), clarithromycin (CLR), cefixime (CFM) and Penicillin (P10). No zone of inhibition was observed. But it showed unusual diffused zone around the Ak and MEM antibiotic discs. rhl R gene and 16s rRNA gene were characterized and analyzed.

CONCLUSION

Findings from current study would help in raising awareness about antibiotic resistance of P. aeruginosa, and also the sequence of rhl R gene can be used as the diagnostic marker sequence to identify the virulent rhl R gene sequence from the samples when isolated from sputum of Pneumonia patients.

Evaluation and reinforcement of the correlation of S-phase fraction with nodal metastases, tumor grade and tumor size in breast carcinoma patients in Pakistan

The aim of this study was to evaluate the S-phase fraction (SPF) of tumors in breast cancer patients in Pakistan. Its association with the traditional morphological prognostic markers, i.e., axillary lymph node metastasis, tumor size and grade, was also studied. Flow cytometry was used to estimate SPF on breast cancer tissues from 166 patients reported at the Aga Khan University Hospital between the years 1997 and 2000. Univariate analysis was done to find any association between SPF and the aforesaid variables. For the ease of analysis, the cases were subdivided into two categories depending on the SPF value, i.e., <10% (low-risk group) and > or = 10% (high-risk group). The mean and median SPF values were 21.45% and 20.035%, respectively, with a range of 3.26% to 54.30%. Twenty-six (15.66%) of the cases had SPF <10%, 57 (34.34%) had SPF from 10%-20%, and 83 (50%) had SPF >20%. A significant correlation between SPF and nodal metastasis was observed (p = 0.0111), but not between SPF and the number of lymph nodes involved when metastatic cases were subdivided into <4 lymph node-positive cases and > or =4 lymph node-positive cases. Significant correlations were also found between SPF and tumor grade (p = 0.0244), as well as between SPF and tumor size (p = 0.048). In conclusion, DNA flow cytometric analysis of SPF carried out in our laboratory could reasonably predict the chances of lymph node metastasis, tumor grade and size in breast cancer patients, thus proving to be an important prognostic marker in the Pakistani setting. This requires further investigations regarding the survival of patients so as to evaluate its capacity of predicting the outcome of Pakistani patients.

Dose-response study of intracoronary beta-radiation with 32P in balloon- and stent-injured coronary arteries in swine

PURPOSE

A dose-response study was performed in swine to investigate the vascular effects of 32P over a broad range of doses in order to define the therapeutic window of intracoronary radiotherapy (ICR) with 32P.

METHODS AND MATERIALS

A total of 131 porcine arteries were subjected to balloon injury or stenting followed by 0-36 Gy of ICR from a centered 32P source wire to 1 mm beyond lumen surface or a sham ICR procedure. Animals were euthanized at 4 weeks, and vessels were harvested for histomorphometry.

RESULTS

In the balloon-injured arteries, doses of 7 and 9 Gy did not impact restenosis. At doses of 14-36 Gy, neointima was markedly reduced, with mild dilatation at the highest dose, 36 Gy. In the stent-injured arteries, the lowest dose of 9 Gy failed to reduce neointimal growth, while 14-26 Gy showed the most favorable response.

CONCLUSIONS

ICR with 32P features a broad therapeutic window. Doses of 14-26 Gy to 1 mm beyond lumen surface provided an optimal combination of efficacy and safety. Doses of 7 and 9 Gy were generally ineffective, suggesting a minimum threshold for ICR with 32P to effectively inhibit restenosis.

Long-term effects of intracoronary beta-radiation in balloon- and stent-injured porcine coronary arteries

BACKGROUND

The data on the long-term safety and efficacy of intracoronary beta-radiation in animal models are limited.

METHODS AND RESULTS

A total of 30 coronary arteries in 15 swine were subjected to balloon or stent injury followed by beta-radiation from a centered 32P source (2000 cGy to 1 mm beyond lumen surface) or a sham radiation procedure. The animals received aspirin for 6 months and ticlopidine for 30 days. Five of the 10 animals subjected to radiation died (at 5 days, 7 days, 3 months [n = 2], and 4 months) as a result of layered, occlusive thrombus at the intervention site (3 stent and 2 balloon injury sites). No deaths occurred in the control group. In the surviving animals, balloon-injured and irradiated vessels showed a trend toward larger lumens than controls (2.15 +/- 0.17 versus 1.80 +/- 0.08 mm2, P=0.06) and larger external elastic lamina areas (3.32 +/- 0.21 versus 2.62 +/- 0.10 mm2, P=0.003). In the stent-injured vessels from surviving animals, lumen, neointimal, and external elastic lamina areas were 3.58 +/- 0.33, 3.16 +/- 0.35, and 8.12 +/- 0.42 mm2 for irradiated vessel segments; these values were not different from those in controls (3.21 +/- 0.15, 2.84 +/- 0.27, and 7.76 +/- 0.28 mm2, respectively). Histologically, healing was complete in most survivors, although intramural fibrin and hemorrhage were occasionally seen.

CONCLUSION

In the long-term (6 month) porcine model of restenosis, the inhibition by intracoronary beta-radiotherapy of the neointimal formation that is known to be present at 1 month is not sustained. This lack of effect on neointimal formation after balloon and stent arterial injury is accompanied by subacute and late thrombosis that leads to cardiac death on a background of continuous aspirin but relatively brief ticlopidine treatment.

Intracoronary radiotherapy for prevention of restenosis after percutaneous coronary interventions

More than 50 different pharmacological and mechanical interventions have been tested to date for prevention of vascular restenosis without success. Intracoronary radiotherapy is the first one showing promise of significantly attenuating neointimal proliferation, causing positive vascular remodelling and thus inhibiting restenosis. This promising modality has moved from animal experiments via safety and feasibility testing into the phase of clinical trials of efficacy in large numbers of patients. While ongoing research continues to search for new sources and delivery techniques, currently available technology is being optimized. The randomized clinical trials conducted to date have shown consistently a reduction of target site restenosis rates by 55-79%. Lower incidence of major adverse cardiac events after radiotherapy has also been demonstrated, primarily as a result of reduction in target site and target vessel revascularization rates. However, experimental and clinical research has identified two major complications of this approach: stenosis at the ends of the radiation zone ('edge effect' or 'candywrapper') as well as late thrombosis (beyond 30 days after intervention) of the angioplasty or stent site. If these two adverse effects can be minimized, intracoronary radiotherapy may prove to be a major breakthrough in percutaneous coronary interventions.

Inhibition of restenosis with beta-emitting radiotherapy: Report of the Proliferation Reduction with Vascular Energy Trial (PREVENT)

BACKGROUND

Intracoronary gamma- and beta-radiation have reduced restenosis in animal models. In the clinical setting, the effectiveness of beta-emitters has not been studied in a broad spectrum of patients, particularly those receiving stents.

METHODS AND RESULTS

A prospective, randomized, sham-controlled study of intracoronary radiotherapy with the beta-emitting (32)P source wire, using a centering catheter and automated source delivery unit, was conducted. A total of 105 patients with de novo (70%) or restenotic (30%) lesions who were treated by stenting (61%) or balloon angioplasty (39%) received 0 (control), 16, 20, or 24 Gy to a depth of 1 mm in the artery wall. Angiography at 6 months showed a target site late loss index of 11+/-36% in radiotherapy patients versus 55+/-30% in controls (P:<0.0001). A low late loss index was seen in stented and balloon-treated patients and was similar across the 16, 20, and 24 Gy radiotherapy groups. Restenosis (>/=50%) rates were significantly lower in radiotherapy patients at the target site (8% versus 39%; P:=0.012) and at target site plus adjacent segments (22% versus 50%; P:=0.018). Target lesion revascularization was needed in 5 radiotherapy patients (6%) and 6 controls (24%; P:<0.05). Stenosis adjacent to the target site and late thrombotic events reduced the overall clinical benefit of radiotherapy.

CONCLUSIONS

beta-radiotherapy with a centered (32)P source is safe and highly effective in inhibiting restenosis at the target site after stent or balloon angioplasty. However, minimizing edge narrowing and late thrombotic events must be accomplished to maximize the clinical benefit of this modality.

Use of nitric-oxide-eluting polymer-coated coronary stents for prevention of restenosis in pigs

BACKGROUND

Restenosis after angioplasty remains an unresolved problem despite an increase in use of coronary stents. It has been theorized that nitric oxide (NO) exerts several actions that can prevent restenosis. These include inhibition of proliferation of smooth muscle cells, prevention of arterial spasms, and decreasing aggregation of platelets in response to exposure to collagen.

OBJECTIVE

To determine whether NO coated stents decrease restenosis in a pig balloon injury model.

METHODS

We used coronary stents impregnated with a slow-release precursor of NO in the porcine model of restenosis. Tantalum coil coronary stents (Cordis) were coated with a polymer impregnated with a slow-release precursor of NO. Polymer-coated stents without active precursors were used as controls. Oversized stents were mounted on a delivery balloon and subsequently deployed in the right coronary and left anterior descending arteries of each animal.

RESULTS

Repeated recording of angiograms demonstrated that changes in minimum lumen diameter on going from immediately after stenting to 28-day follow-up for the control and NO-eluting-stent groups were similar, namely decreases of 1.89 +/- 0.33 and 2.08 +/- 0.28 mm, respectively. The morphometric results, showing that severe luminal narrowing occurred for both groups, were similar. The percentage area stenoses were 85 +/- 5% for the control group and 84 +/- 6% for the NO-eluting group. Histology demonstrated that profuse formation of neointima and an inflammatory cell infiltrate occurred.

CONCLUSIONS

Severe diameter stenosis occurred both for control and for treatment groups. The degree of angiographic stenosis was markedly worse than that previously reported for this model. Sustained release of a precursor of NO did not prevent restenosis in this model. This might have been due to a lack of efficacy of nitric oxide or to a profuse and overwhelming stimulatory effect of the polymer in the coated stents.

Intraperitoneal lidocaine for postoperative pain after laparoscopy

BACKGROUND

A controversy exists over the effectiveness and clinical value of intraperitoneal local anaesthetics for treating pain after laparoscopic cholecystectomy. The use of intraperitoneal lidocaine was evaluated in this study.

METHODS

At the end of surgery, 200 ml saline containing 200 mg lidocaine, or the same volume of saline, were randomly splashed under the right diaphragmatic surface in 50 patients in a double-blind manner. Postoperative shoulder and abdominal pain intensity were recorded on a numeric grading scale and a visual analogue scale, respectively. Analgesic consumption was also recorded. Respiratory function tests were compared before and after surgery. Side effects and recovery variables were assessed by the nurses at 2-h intervals.

RESULTS

The incidence, severity and duration of shoulder pain were reduced from 40% of patients scoring 3.9+/-0.2 for duration of 17.9+/-0.2 h in the control group to 12% scoring 2.5+/-0.5 for duration of 1.6+/-0.01 h in the lidocaine group. Lidocaine treated patients had significantly less abdominal postoperative pain immediately on return to the ward and during the first postoperative day (P<0.05). "No pain on deep inspiration" was reported by 72% of patients in the lidocaine group immediately on return to the ward compared to 8% of those in the control group. Analgesic consumption for 24 h after surgery was significantly less in the lidocaine group (P<0.05). There were no significant differences in respiratory function tests, recovery variables or incidence of side effects between the two groups.

CONCLUSION

Intraperitoneal lidocaine is simple to use and results in a long-lasting reduction of pain after a single administration.

A randomized EPOCH vs. CHOP front-line therapy for aggressive non-Hodgkin's lymphoma patients: long-term results

BACKGROUND

The value of continuous-infusion chemotherapy (EPOCH) vs. the standard CHOP combination was evaluated in 78 patients with previously untreated aggressive non-Hodgkin's lymphoma in a randomized phase III clinical trial.

PATIENTS AND METHODS

The EPOCH regimen given to 38 patients consisted of the drugs etoposide (50 mg/m2), vincristine (0.4 mg/m2), and doxorubicin (10 mg/m2), all given in a continuous infusion on days 1-4. Cyclophosphamide (750 mg/m2) was administered on day 6 as i.v. bolus, while prednisone was given orally 60 mg/m2 on days 1-6. Courses were repeated every three weeks. CHOP was given to 40 patients as routinely prescribed.

RESULTS

Forty-eight patients were males and thirty were females. Their ages ranged from 19-75 years (median 45 years). Forty-three (55%) had grade 2 and thirty-five (45%) had grade 3 pathologic subtype. Nine patients (12%) presented with stage I, fourteen (18%) with stage II, forty (51%) with stage III, and fifteen (19%) with stage IV disease. The different clinico-pathologic characteristics, including international index categories, were comparable in the two groups. The number of courses given ranged between 3 and 9 (median 6) for both the EPOCH and CHOP regimens. Complete remission (CR) was achieved in 19 (50%), and 27 (67%) of the 38 and 40 patients for both the EPOCH and CHOP combinations, respectively. After a median observation time of 27 months, the four-year overall and failure-free survival rates were 42% and 30% for the EPOCH and 71% and 54% for the CHOP regimen (P = 0.006 and 0.1 for the overall and FFS rates, respectively). Toxicities were comparable and were mostly of grades 1 and 2, except for hair loss, hematologic toxicities, and infectious episodes which were more common in the EPOCH group. In the EPOCH group, overall survival rates were 55% vs. 22% (P < 0.04) at four years for the low-risk (2 prognostic factors) and high-risk (> 2 factors) groups, respectively.

CONCLUSIONS

Thus, it may be concluded that continuous-infusion (EPOCH) chemotherapy did not improve treatment outcome over that of the CHOP regimen for aggressive non-Hodgkin's lymphoma patients.

Clinical experience with a spiral balloon centering catheter for the delivery of intracoronary radiation therapy

PURPOSE

To develop and evaluate an intravascular radiation delivery catheter that incorporates a centering mechanism and that allows side branch and distal artery perfusion.

METHODS AND MATERIALS

The Galileo Centering Catheter (Guidant Vascular Interventions, Houston, TX) incorporates a rapid exchange tip design. A unique spiral balloon allows centering and facilitates perfusion to the distal artery and side branches. The catheter contains a dedicated dead-end lumen for source wire delivery to the lesion site. The treatment area is precisely defined by radiopaque markers.

RESULTS

In three clinical trials to date, radiation (or placebo) was delivered successfully to 300 of 312 patients (96%). With balloon inflation, TIMI grade 2 or 3 flow was achieved in side branches in 82% and in the distal artery in 77% of patients. Despite treatment (dwell) times ranging from 87 to 948 s (mean = 250 s), only 8% of patients required fractionation of treatment.

CONCLUSION

The Galileo Centering Catheter is a safe and highly effective method for delivering intracoronary radiation therapy. Its unique design provides centering of the source while allowing side branch and distal coronary perfusion during treatment. This catheter would facilitate intracoronary radiation therapy and allow uniform and reproducible dose delivery to the target in the artery wall.

A cluster of transfusion-associated babesiosis cases traced to a single asymptomatic donor

CONTEXT

The risk of acquiring babesiosis by blood transfusion is largely unknown since in areas where it is endemic it is often an asymptomatic infection.

OBJECTIVE

To investigate and treat a cluster of blood transfusion-associated babesiosis cases.

DESIGN

Case series and epidemiologic investigation.

SETTING

Urban inner-city hospital.

PATIENTS

Six persons who received Babesia microti-infected blood components from a donor.

MAIN OUTCOME MEASURE

Diagnosis and successful therapy of babesiosis following transfusion.

RESULTS

Six individuals (1 adult, 1 child, and 4 neonates) were exposed to products from a single blood donation by an asymptomatic Babesia-infected donor. Three of the 6 exposed patients became parasitemic. Polymerase chain reaction testing, animal inoculation studies, and indirect immunofluorescent antibody testing were used to confirm the presence of Babesia microti in the donor's blood and to establish the presence of infection in 3 of the 6 recipients. The 3 infected recipients and 1 additional recipient were treated without incident.

CONCLUSION

Physicians should consider babesiosis in the differential diagnosis of a febrile hemolytic disorder after blood transfusion. Prompt diagnosis is important since babesiosis is responsive to antibiotic therapy and, untreated, can be a fatal disease in certain risk groups.

Exchange transfusion with red blood cells preserved in adenine clears a child of severe falciparum malaria

Falciparum malaria may be associated with significant morbidity and mortality. The degree of mortality and morbidity usually corresponds to the degree of parasitemia. Quinine and other antimalarial drugs are relatively slow acting and not always effective owing to the presence of drug resistance falciparum. Rapid reduction of the number of circulating parasites may be required. Exchange transfusion has been used as a safe and quick approach to decreasing the parasitemia and antimalaria drugs used to eradicate the rest of the Plasmodium. In the present report, a case is described of a child with severe falciparum malaria who was successfully treated with exchange transfusion using the new adenine and mannitol enriched preservative media, Adsol.

Pathogenesis of pulmonary aspergillosis. Granulocytopenia versus cyclosporine and methylprednisolone-induced immunosuppression

Patients with chemotherapy-induced granulocytopenia for neoplastic diseases and those receiving cyclosporin A plus corticosteroids for prevention and treatment of organ transplant rejection are two immunologically distinct patient populations with high risks for development of invasive pulmonary aspergillosis. In order to compare the pathogenesis of aspergillosis in these two high-risk populations and to further characterize the role of cyclosporin A in development of pulmonary aspergillosis, we studied the patterns of infection and inflammation in two clinically applicable rabbit models of invasive pulmonary aspergillosis. There were striking differences in the patterns of infection and inflammation of invasive pulmonary aspergillosis according to the type of underlying immune defect. Among rabbits challenged with the same intratracheal inoculum, there was a 100% mortality for invasive pulmonary aspergillosis in profoundly granulocytopenic rabbits in comparison with a 100% mortality for invasive pulmonary aspergillosis in profoundly granulocytopenic rabbits in comparison with a 100% survival in rabbits immunosuppressed with cyclosporin A plus methylprednisolone (CsA+MP). Lesions of pulmonary aspergillosis in granulocytopenic rabbits consisted predominantly of coagulative necrosis, intraalveolar hemorrhage, and scant mononuclear inflammatory infiltrate. By comparison, pulmonary foci in rabbits immunosuppressed by CsA+MP consisted mainly of neutrophilic and monocytic infiltrates, inflammatory necrosis, and scant intraalveolar hemorrhage. There was extensive infiltration by hyphae with angioinvasion in granulocytopenic rabbits, whereas conidia in various stages of germination predominated in CsA+MP treated animals in which there was a paucity of hyphae or angioinvasion. Extrapulmonary disease predominated in granulocytopenic rabbits. Methylprednisolone was the major immunosuppressive drug in rabbits treated with CsA+MP. Cyclosporin A alone did not increase the progression of pulmonary aspergillosis and did so only when used chronically with methylprednisolone.

Evaluation of acupuncture and occlusal splint therapy in the treatment of temporomandibular joint disorders

One hundred patients showed signs and symptoms of temporomandibular joint disorder, were participated in a one year follow up study. The patients were randomly divided into four groups: Acuhealth treatment (group A), occlusal splint therapy (group B), Acuhealth and occlusal splint therapy (group C), and control (group D). Each group comprised 25 patients. The patients were examined before and 3, 6, and 12 months after treatment. At the three month evaluation, the patients who were not satisfied with the treatment outcome were offered additional treatment. The result showed that 87% of the patients treated by Acuhealth unit, 77.3% of the patients treated with occlusal splint therapy, and 91.3% of the patients received Acuhealth and occlusal splint therapy were improved subjectively and clinically after 3 months follow-up. The patients who responded well to treatment initially also responded well in the long run. The study showed that the Acuhealth unit proved to be an ideal early therapy for TMD, and complemented later with occlusal splint.

Does sympathetic ganglionic block prevent postherpetic neuralgia? Literature review

BACKGROUND AND OBJECTIVES

To examine specifically the role of sympathetic block in the prevention of postherpetic neuralgia by its application in the treatment of acute herpes zoster.

METHODS

Data sources included a Medline search and cross-referencing of articles and text books. A total of 84 references were reviewed. Peer-reviewed articles were selected according to their relevance to the subject and originality. The data were critically analyzed by the author with the specific intention of avoiding bias.

RESULTS

The opinion of the medical community is divided on the role of sympathetic block in preventing postherpetic neuralgia because of the lack of controlled trials and the conflicting retrospective reports as to its effectiveness. While many reports promote the early use of sympathetic blocks during acute herpes zoster to prevent postherpetic neuralgia, others deny their value.

CONCLUSIONS

Considering the degree of uncertainty, and the seriousness of postherpetic neuralgia, sympathetic block in addition to treatment with acyclovir should be considered early during acute herpes zoster. Large controlled trials are needed to provide the necessary scientific evidence.

Fate of side branches after intracoronary implantation of the Gianturco-Roubin flex-stent for acute or threatened closure after percutaneous transluminal coronary angioplasty

Side branch occlusion may occur in the course of percutaneous transluminal coronary angioplasty (PTCA), particularly if complicated by site dissection. Concern that the additional placement of a stent may further jeopardize side branches is logical. Consequently, this study analyzed pre-PTCA, post-PTCA, poststent, and 6-month follow-up angiograms of 100 consecutive patients in whom 103 Gianturco-Roubin stents were implanted for acute or threatened closure after PTCA. Side branches were defined as major (> 50% of the stented vessel diameter) and minor (< 50%). Minor branches, often < 1 mm in diameter, were assessed only for patency. One hundred eight major branches, of which 33 were diseased (> 50% stenosis), and 129 minor branches were analyzed. Seven major branches (6%), all of which were diseased before PTCA, and 23 minor branches (18%) were lost after PTCA. Immediately after stent insertion, only 1 additional major and 1 minor branch were lost, whereas 2 of 7 major (29%) and 9 of 23 minor (39%) branches reappeared. At follow-up angiography, 7 major branches (6%) were more stenosed and 6 (6%) were improved compared with the angiogram before PTCA. Only 2 major (2%) and 5 minor (4%) branches remained occluded. Additionally, 2 major and 1 minor branch, which were patent after PTCA and stenting, were occluded at follow-up as a result of total occlusion of the stented segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous transluminal in vivo gene transfer by recombinant adenovirus in normal porcine coronary arteries, atherosclerotic arteries, and two models of coronary restenosis

BACKGROUND

Gene therapy has been proposed as a possible solution to the problem of restenosis after coronary angioplasty. The current study was undertaken to assess conventional methods of gene transfer and to develop percutaneous techniques for introducing genes directly into the coronary arteries of large mammals. Since the anticipated targets of gene therapy against restenosis include atherosclerotic and previously instrumented arteries, we also evaluated gene transfer in atherosclerotic coronary arteries and in two porcine models of restenosis: one using intracoronary stents and a second using balloon overstretch angioplasty.

METHODS AND RESULTS

The conventional method of using perforated balloon catheters to deliver Lipofectin-DNA complexes directly into the coronary arteries of intact animals was applied to 18 porcine coronary arteries including normal arteries, hypercholesterolemic arteries, and those simulating restenosis. The results of this study were consistent with previously published results indicating that only low levels of luciferase gene expression could be obtained by Lipofectin-mediated gene transfer. We therefore undertook a second, parallel study to evaluate percutaneous transluminal in vivo gene transfer using a replication-deficient adenoviral vector. A comparison of the two studies revealed that the mean level of reporter gene expression in the cohort undergoing adenoviral infection was 100-fold higher than in the cohort undergoing Lipofection. Analysis of luciferase activity over time in normal arteries revealed that recombinant gene expression was half-maximal after 1 day, peaked within 1 week, was still half-maximal at 2 weeks, and declined to low levels by 4 weeks. Histochemical analysis of coronary arteries treated with a second adenovirus expressing a nuclear-localized beta-galactosidase gene demonstrated gene transfer to a limited number of cells in the media and adventitia. Immunohistochemical analysis of Ad5-infused arteries using a monoclonal antibody directed against CD44 identified a periadventitial infiltrate composed of leukocytes.

CONCLUSIONS

The recombinant adenoviral vectors proved to be far more effective than Lipofectin at delivering foreign genes directly into the coronary arteries of living mammals. Furthermore, the influences of hypercholesterolemia and arterial injury appeared to have little effect on the levels of gene expression obtained using either method. The results demonstrate that low-level recombinant gene expression, the major obstacle impeding gene therapy for the prevention of restenosis, can potentially be overcome by using adenoviral vectors to mediate coronary gene transfer in vivo. The duration of gene expression provided by these vectors and their effective deployment in atherosclerotic, balloon-overstretched, and stented coronary arteries suggest that recombinant adenovirus may have potential for evaluating gene therapy in the clinically informative porcine models of coronary restenosis.

Lipofectin-mediated versus adenovirus-mediated gene transfer in vitro and in vivo: comparison of canine and porcine model systems

BACKGROUND

Restenosis after coronary angioplasty might be prevented by locally delivered gene therapy in conjunction with percutaneous transluminal coronary angioplasty (PTCA), since this approach should provide a sustained source of therapeutic protein within the dilated lesion. However, the potential application of gene therapy is limited by the technical barrier of efficiently transferring genes to vascular cells.

METHODS

We used cultured coronary smooth muscle cells of human, porcine, and canine origin to evaluate three methods of gene transfer: recombinant adenovirus, liposomal complexes (Lipofectin), and Lipofectin supplemented with hemagglutinin. We then compared Lipofectin- and adenovirus-mediated direct gene transfer in canine and porcine coronary arteries.

RESULTS

The lipofection of cultured smooth muscle cells was enhanced by adding hemagglutinin, yielding luciferase levels that were 631-fold (human), ninefold (porcine), and sevenfold (canine) higher than with Lipofectin alone. However, the recombinant adenovirus directed even higher levels of gene expression, yielding luciferase levels that were 113,000-fold (human), 450-fold (porcine), and 230-fold (canine) higher than with Lipofectin alone. After percutaneous transluminal local delivery to intact canine coronary arteries, the adenovirus produced 55 times more luciferase than did Lipofectin. In living porcine coronary arteries, adenovirus produced 95 times more luciferase than did Lipofectin.

CONCLUSION

Recombinant adenovirus produces far more recombinant protein than does Lipofectin after percutaneous transluminal direct gene transfer to canine and porcine coronary arteries. Adenoviral vectors may therefore prove useful in evaluating the potential of gene therapy in large animal models of coronary restenosis.

Itraconazole for experimental pulmonary aspergillosis: comparison with amphotericin B, interaction with cyclosporin A, and correlation between therapeutic response and itraconazole concentrations in plasma

Itraconazole and amphotericin B were compared by using a newly developed model of invasive pulmonary aspergillosis in rabbits immunosuppressed with methylprednisolone and cyclosporin A (CsA). Both itraconazole at 40 mg/kg (given orally) and amphotericin B at 1 mg/kg (given intravenously) had in vivo antifungal activity in comparison with controls. At these dosages, amphotericin B was more effective than itraconazole in reducing the tissue burden (log10 CFU per gram) of Aspergillus fumigatus (P < 0.05) and the number of pulmonary lesions (P < 0.01). However, there was considerable variation in the near-peak concentrations of itraconazole in plasma (median, 4.15 micrograms/ml; range, < 0.5 to 16.8 micrograms/ml) and a strong inverse correlation between concentrations of itraconazole in plasma and the tissue burden of A. fumigatus. An inhibitory sigmoid maximum-effect model predicted a significant pharmacodynamic relationship (r = 0.87, P < 0.001) between itraconazole concentrations in plasma and antifungal activity as a function of the tissue burden of A. fumigatus. This model demonstrated that levels in plasma of greater than 6 micrograms/ml were associated with a significantly greater antifungal effect. Levels in plasma of less than 6 micrograms/ml were associated with a rapid decline in the antifungal effect. Itraconazole, in comparison with amphotericin B, caused a twofold elevation of CsA levels (P < 0.01) but was less nephrotoxic (P < 0.01). This study of experimental pulmonary aspergillosis demonstrated that amphotericin B at 1 mg/kg/day was more active but more nephrotoxic than itraconazole at 40 mg/kg/day, that itraconazole increased concentrations of CsA in plasma, and that the antifungal activity of itraconazole strongly correlated with concentrations in plasma in an inhibitory sigmoid maximum-effect model. These findings further indicate the importance of monitoring concentrations of itraconazole in plasma as a guide to increasing dosage, improving bioavailability, and optimizing antifungal efficacy in the treatment of invasive pulmonary aspergillosis.

Coronary restenosis and gene therapy

Restenosis continues to limit the efficacy of coronary angioplasty, despite the various mechanical and pharmaceutical interventions that have been employed. The migration, proliferation, and extracellular matrix production by vascular smooth muscle cells are processes integral to restenosis, and sustained local delivery of drugs at high concentration should curtail these vascular responses to balloon angioplasty. Our laboratory and others are exploring the potential of using somatic cell gene therapy to provide such treatment and thereby prevent restenosis. However, conventional methods of gene transfer fail to produce physiologic levels of recombinant protein in vivo. This obstacle might be overcome by using adenoviral vectors to mediate efficient direct gene transfer. Herein we summarize these developments and focus upon our laboratory's progress towards evaluating adenovirus-mediated gene therapy in porcine coronary arteries. Recombinant adenoviruses directing the expression of the beta-galactosidase and luciferase reporter genes were evaluated in cultured coronary vascular smooth muscle cells in vitro and in porcine coronary arteries in vivo. Following percutaneous transluminal gene transfer in vivo, recombinant adenoviruses were shown to produce 70- to 240-fold more reporter protein than that produced by Lipofectin-DNA complexes. Furthermore, the high levels of adenovirus-mediated gene expression were shown to persist for at least 14 days following catheterization. Additional histologic studies will be required to determine the cellular distribution of gene expression and to elucidate potential interactions between adenovirus and the host's immune system, but recombinant adenovirus appears to be a promising vector for evaluating gene therapy against coronary restenosis.

Directional atherectomy with the Omnicath: a unique new catheter system

Omnicath is a directional atherectomy catheter that employs deflecting nontraumatizing wires to anchor the cutting window at the atherectomy site. This anchoring system regulates the depth of cut and provides directional control and distal perfusion. The system continuously removes debris through a suction port from the operative site. To demonstrate the performance of the device, the Omnicath was tested in the external iliac arteries of ten atherosclerotic Hanford miniature swine in which concentric and eccentric lesions were induced. Five animals were sacrificed 3 days after atherectomy; the remaining five animals were sacrificed 6 weeks after the procedure. The acute histology demonstrates depth of cuts varying from partial plaque removal to near full thickness removal of the arterial wall. Histologic sections of the 6 week follow-up group demonstrated minimal healing response. The anchoring wires did not induce either acute injury or neointimal proliferation in the 6 week follow-up period. In conclusion, the Omnicath permits effective and safe atherectomy in this investigative model.

A randomized pilot study of high-dose epirubicin as neoadjuvant chemotherapy in the treatment of cancer of the bilharzial bladder

Seventy-one patients with T2 and T3 bladder cancer were randomized to receive either two courses of epirubicin 120 mg/m2 i.v. push every 21 days pre-operatively, and four additional courses post-operatively (group I = 34 patients), or radical surgery (group II = 37 patients). At a median follow-up of 24 months (range 22 months to 38 months) 25 patients from group I and 14 patients from group II are still alive and disease-free. The estimated two-year disease-free survival percentages were 73.5 and 37.9%, respectively (P = 0.05). After initial chemotherapy, resected specimens were subjected to histopathological study of chemotherapeutic effects. Necrosis was detected in 95% of cases with squamous cell carcinoma and in 57.3% of cases with transitional cell carcinoma. We conclude that the benefit which was obtained by pre-operative and post-operative chemotherapy with epirubicin is promising and may represent a significant improvement in the treatment of patients with carcinoma of the bilharzial bladder.

Tolerance during long-term administration of intrathecal morphine

We studied the time course of development of tolerance in four terminally ill cancer patients who were treated for intractable pain by intrathecal morphine administered by an implanted catheter and pump. The duration of treatment varied from 1.8 to 10.5 months. Our study shows that with disease progression, there was a constant patient-specific time rate of increase in the morphine dose requirements. Hence, for any given patient, the slope of the dose v time curve is effectively a constant over long periods. We also found that patients tolerate very high doses of intrathecal morphine without serious side effects.

Percutaneous epidural catheterization for intractable pain in terminal cancer patients

We examined the effects of long-term percutaneous epidural catheterization for pain relief in nine terminally ill gynecologic cancer patients. All patients were free of side-effects such as respiratory depression, nausea, vomiting, urinary retention, or pruritus. Analgesia was excellent in six patients. Puncture-site skin inflammation occurred in four patients. Catheter dislodgement occurred in three patients. Although percutaneous epidural catheters were well tolerated in a few patients for an extended period of time, the frequency of catheter problems demonstrate that other methods such as catheter tunneling or implantable systems should be considered for long-term epidural administration of narcotics. This method appears to be most effective in patients suffering from pain due to nerve root involvement.

Observations on the gross changes in the secondary lymphoid organs of mice infected with Nematospiroides dubius

Gross changes in the size of the secondary lymphoid organs were studied during infection with the nematode parasite Nematospiroides dubius. In the strong responder NIH strain, the wet weight of the mesenteric lymph nodes (MLN) increased rapidly following infection with 400 larvae to peak on day 28 at approximately three times the resting weight. Enlargement of the spleens was also marked but regression to normal size took place when the MLN had achieved maximum size. In contrast in C57BL/10 mice, a slow responder strain, the enlargement of the MLN following infection was relatively slow, and there was no evidence of the regression of the spleen, once maximum enlargement had been achieved. When adult worms were removed by anthelmintic, the enlarged MLN and spleens returned rapidly to normal size. However, in mice infected with irradiated larvae (25 krad) the MLN stayed enlarged, despite the absence of adult worms but the spleens of these mice returned to normal size fairly rapidly. It was suggested that irradiated worms survive, perhaps as arrested larvae in the intestinal tissue, for a fairly long time, thereby providing a continual stimulus for the MLN.

The pattern of peripheral blood leucocyte changes in mice infected with Nematospiroides dubius

Experiments were carried out to define the haematological changes taking place during the first six weeks of a primary infection with Nematospiroides dubius. The general pattern of changes was observed to comprise a rapid increase in circulating leucocytes (4 to 5-fold increase) which consisted of a neutropl a, lymphocytosis, monocytosis and an eosinophilia. However, in strong responder NIH mice leucocyte counts returned to normal more rapidly than in other strains (by day 28). In contrast, in weak responder C57BL/10 mice the leucocyte counts whilst falling significantly relative to day 7 did not return to normal within the experimental period. Mice infected with irradiated larvae did not experience as high a leucocytosis as did mice given an identical number of normal larvae. The peak lymphocytosis, neutrophilia and monocytosis were all lower. The removal of adult worms from infected animals by treatment with pyrantel on days 9, 11, 13 and 16, also significantly altered the pattern of leucocytosis. The neutrophilia which was evident on day 7 returned rapidly to normal, whereas in mice which had retained their worms a peak neutrophilia was observed on day 14. These haematological changes were discussed and related to the failure of host-protective immunity to operate effectively during the early stages of a primary infection with N. dubius.

Effect of feeding on the fate of orally administered phenylbutazone, trimethoprim and sulphadiazine in the horse

Phenylbutazone, sulphadiazine and trimethoprim were administered to three horses on two occasions, recently fed and unfed, and the effect of feeding on the pharmacokinetics of the three drugs assessed. The mean peak concentrations of phenylbutazone and trimethoprim were reduced by feeding by 34 and 75 per cent, respectively. The pharmacokinetics of sulphadiazine were not significantly affected.

Survival to patency of low level infections with Trichuris muris in mice concurrently infected with Nematospiroides dubius

Large, single-pulse laboratory infections with Trichuris muris are rejected by mice before patency, but low-level infections of fewer than 20 worms survive for long periods. Data are presented to show that the threshold at which an effective immune response takes place is significantly higher in mice concurrently infected with Nematospiroides dubius. In control CFLP mice trickle infections did not survive to maturity but in the slower responder C57 Bl10 mice egg production began on Day 35 and continued for a further seven weeks, with some mature worms present at autopsy. Concurrent infection with N. dubius resulted in trickle infections, T. muris surviving much better than in control mice, although these still showed some resistance to T. muris. It is suggested that the results support the hypothesis that T. muris elicits concomitant immunity in the host. Thus, the first worms to establish survive to patency at which time they can no longer be removed by the host, but once the immunological threshold has been exceeded incoming larvae are rejected by the host. Such a survival strategy would be very useful to T. muris in the wild.

Analysis of the mechanism of immunodepression following heterologous antigenic stimulation during concurrent infection with Nematospiroides dubius

The suppression of immune responsiveness to heterologous antigenic stimulation during concurrent infection with Nematospiroides dubius was reproduced using soluble antigens derived from adult parasites. Immunosuppression appeared to be selective in that the administration of equivalent quantities of an irrelevant heterogeneous antigen had no immunosuppressive effect, and suppression was transferable using spleen cells from parasite antigen-treated donors. The differential immunomodulatory activity of parasite antigens from a variety of nematode species suggested that a correlation might exist between suppressor activity and chronicity of infection. A role for suppressor T cell activity in the infected host was implicated by the restorative effect of 2'deoxyguanosine treatment on the immune response, and non-specific suppressor cell activity was detected in splenocyte populations from infected mice. It is suggested that a parasite-induced defect in antigen processing led to the induction of suppressor cell activity in the infected host and that this may be one mechanism of parasite survival. The relevance of these observations to vaccination against chronic gastrointestinal nematode infections is discussed.

Non-specific immunodepression by larval and adult Nematospiroides dubius

Mice infected with Nematospiroides dubius generate weaker immune responses to concurrently administered sheep red blood cells (SRBC), than non-infected controls. The experiments described in this paper demonstrate that both adult and larval stages of N. dubius cause non-specific immunodepression of the response to SRBC. Mice which had been infected with larvae exposed to 25 krad. of irradiation, which prevents development to the adult luminal stages, produced as weak haemagglutination responses to SRBC as mice infected with normal worms even when SRBC were administered 6 weeks after infection. The removal of adult N. dubius by treatment with pyrantel 9, 11 and 15 days after infection with normal larvae did not restore the host's ability to respond to SRBC given on day 14. It was only when the mice had been without worms for 17 days that their capacity to respond normally to SRBC was restored. Mice infected with 60 or 400 transplanted adult worms produced depressed haemagglutination and plaque-forming responses to concurrently injected SRBC when compared with normal or sham-operated controls. The significance of these results is discussed in relation to the possible role of non-specific immunodepression in facilitating the survival of N. dubius in the host.

Nematospiroides dubius: factors affecting the primary response to SRBC in infected mice

Mice infected with Nematospiroides dubius were incapable of responding normally to i.p. or i.v. challenge with SRBC. The HA and PFC response to SRBC in infected animals was characterized by a severe depression of antibody to SRBC on day 4 and a reduced HA peak titre during the following week. The greatest depression of the response to SRBC was associated with an interval of 14 days between infection and the administration of antigen, suggesting that a particular stage of the parasite contributed significantly to immunodepression during this critical period. It was proposed that a combination of parasite induced damage to the intestine, release of parasite secretory/excretory products and loss of appetite by the host produced trauma during which the host was incapable of responding normally. However, mice given low-level and long-standing infections also showed reduced responses to SRBC, although these animals were not severely depressed. It is possible that this generalized weakening of host immunocompetence is the inevitable consequence of a parasite mechanism which operates more specifically to suppress the expression of homologous immunity at the intestinal level.

Safety and efficacy of atracurium (BW33A) in surgical patients receiving balanced or isoflurane anesthesia

Atracurium was administered in a dose range of 0.027-0.4 mg/kg and dose-response curves were established for both balanced and isoflurane anesthetic techniques. With balanced anesthesia, ED50 and ED95 were 0.12 and 0.27 mg/kg, respectively, while with isoflurane they were 0.07 and 0.13 mg/kg and the least-squares regression line R2 values were 0.71 and 0.64, respectively. With balanced anesthesia there was a significant increase in systolic blood pressure at the 0.04 mg/kg dose (P = 0.02), while with isoflurane the systolic and diastolic blood pressures decreased at the 0.3 mg/kg dose (P less than 0.03). These changes were clinically insignificant. Atracurium is a potent nondepolarizing muscle relaxant which is potentiated by isoflurane. Its cardiovascular effects appear clinically nonsignificant. There is no evidence of histamine release.