Detection and genomic characterization of Klebsiella pneumoniae and Escherichia coli harboring tet(X4) in black kites (Milvus migrans) in Pakistan

The emergence of plasmid-mediated tigecycline resistance gene tet(X4) among clinically relevant bacteria has promoted significant concerns, as tigecycline is considered a last-resort drug against serious infections caused by multidrug-resistant bacteria. We herein focused on the isolation and molecular characterization of tet(X4)-positive Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. coli) in wild bird populations with anthropogenic interaction in Faisalabad, Pakistan. A total of 150 birds including black kites (Milvus migrans) and house crows (Corvus splendens) were screened for the presence of tigecycline resistance K. pneumoniae and E. coli. We found two K. pneumoniae and one E. coli isolate carrying tet(X4) originating from black kites. A combination of short- and long-read sequencing strategies showed that tet(X4) was located on a broad host range IncFII plasmid family in K. pneumoniae isolates whereas on an IncFII-IncFIB hybrid plasmid in E. coli. We also found an integrative and conjugative element ICEKp2 in K. pneumoniae isolate KP8336. We demonstrate the first description of tet(X4) gene in the WHO critical-priority pathogen K. pneumoniae among wild birds. The convergence of tet(X4) and virulence associated ICEKp2 in a wild bird with known anthropogenic contact should be further investigated to evaluate the potential epidemiological implications. The potential risk of global transmission of tet(X4)-positive K. pneumoniae and E. coli warrant comprehensive evaluation and emphasizes the need for effective mitigation strategies to reduce anthropogenic-driven dissemination of AMR in the environment.

AB1586-PARE MULTI-CENTER, RANDOMIZED, OPEN-LABEL, 2-ARM PARALLEL STUDY TO COMPARE THE PHARMACOKINETICS, SAFETY AND TOLERABILITY OF AVT02 ADMINISTERED SUBCUTANEOUSLY VIA PREFILLED SYRINGE OR AUTOINJECTOR IN HEALTHY ADULT VOLUNTEERS

Background

AVT02 is an investigational biosimilar to adalimumab. It is approved in Europe, Canada, and the UK. It is not approved by the US Food and Drug Administration (FDA).

Objectives

To evaluate the pharmacokinetic similarity of 100 mg/mL AVT02, an investigational biosimilar of adalimumab, when administered either via a pre-filled syringe, or with a newly developed autoinjector in healthy adult subjects.

Methods

This was a Phase 1, randomized, open-label, parallel-group study in which 207 healthy adult subjects were randomized in a 1:1 ratio to receive 100 mg/mL AVT02 either via a pre-filled syringe, or with an autoinjector, stratified by body weight. Subjects received a single subcutaneous 40 mg dose on Day 1. Pharmacokinetics, immunogenicity, local injection site reactions, and adverse events were assessed prior to, and up to 64 days after, study drug administration.

Results

The results observed supported the assessment of pharmacokinetic similarity of investigational AVT02 administered by pre-filled syringe or with an autoinjector. The 90% CIs for the ratios of geometric least square means for the primary pharmacokinetic parameters Cmax, AUC0-t, and AUC0-∞ were contained within prespecified margins 80% and 125%, based on an analysis of variance model with treatment as a fixed effect. The mean serum concentration-time profile of adalimumab by treatment group is shown in Figure 1.

Figure 1.

Mean Serum Concentration-Time Profile of Adalimumab by Treatment Group on Semilogarithmic Scale (Pharmacokinetic Population)

Binding anti-drug antibodies were detectable at the end of study visit on Day 64 in 100% and 97.0% of subjects in the pre-filled syringe administration and the autoinjector groups, respectively. Of those subjects positive for anti-drug antibodies, 85.7% and 86.5% further tested positive for neutralizing antibodies in the pre-filled syringe administration and autoinjector groups, respectively. The frequency of local administration site reactions was 11.8% overall and similar between treatment groups. The most frequently reported treatment-emergent adverse events in both treatment groups were under the SOC: Infections and infestations (56.0% in the AVT02-pre-filled syringe group and 45.2% in the AVT02-autoinjector group). The safety profiles were generally similar between treatment groups.

Conclusion

The results observed supported the assessment of pharmacokinetic similarity between the pre-filled syringe and autoinjector delivery systems after a single subcutaneous 40 mg dose. The autoinjector delivery system was generally well tolerated in healthy subjects, with a safety and immunogenicity profile similar to that observed with 100 mg/mL AVT02 administered using a pre-filled syringe.

ClinicalTrials.gov Identifier: NCT03983876

Disclosure of Interests

Christopher Wynne: None declared, Heimo Stroissnig Employee of: Alvotech, Roshan Dias Employee of: Alvotech, Joanna Sobierska Employee of: Alvotech, Eric Guenzi Employee of: Alvotech, Hendrik Otto Employee of: Alvotech, Abid Sattar Employee of: Alvotech, Halimu N. Haliduola Employee of: Alvotech, Elin Edwald Employee of: Alvotech, Fausto Berti Employee of: Alvotech

AB0350 ASSESSMENT OF REAL-LIFE PATIENT HANDLING EXPERIENCE OF AVT02 ADMINISTERED SUBCUTANEOUSLY VIA AUTOINJECTOR IN PATIENTS WITH MODERATE-TO-SEVERE ACTIVE RHEUMATOID ARTHRITIS: AN OPEN-LABEL, SINGLE-ARM CLINICAL TRIAL, THEN AN EXTENSION PHASE OF AVT02 ADMINISTERED WITH A PRE-FILLED SYRINGE (ALVOPAD-PEN)

Background

AVT02 is an investigational biosimilar to adalimumab. It is approved in Europe, Canada, and the UK. It is not approved by the US Food and Drug Administration (FDA).

Objectives

To assess the real-life patient handling of an autoinjector (AI) in adult patients with moderate-to-severe active rheumatoid arthritis (RA) who self-inject AVT02 subcutaneously (s.c.).

Methods

This open-label study enrolled 107 adalimumab-naïve subjects with moderate-to-severe active RA to self-inject AVT02 with the proposed AI 40 mg s.c. in Week 1, and every other week thereafter through Week 8. In an optional extension phase through Week 56, subjects were switched from AVT02 AI to pre-filled syringe and followed for safety and efficacy. The primary endpoint was the percentage of successful self-injections as reported by both the trial site and by subjects using standardized questionnaires at Week 8. Additional endpoints included ease of use and robustness of the AI at Week 8, and efficacy in RA, assessment of serum trough levels of AVT02, and detection of antidrug antibodies (ADA) throughout the study.

Results

The AI success rate was 100% as reported by both the trial site and by subjects. No handling events were noted through Week 8. Approximately 80% (78.1–84.9%) of subjects found the AI ‘very easy’ to use and, in general, less difficulty was reported as the study progressed. The first 110 AIs used were inspected for robustness and none showed any sign of damage or malfunction.

All subjects who completed Week 8 (n = 106) took part in and completed the optional extension phase through Week 56.

At Week 8, 49.1%, 5.7% and 0.9% subjects achieved ACR20, -50 and -70 responses, respectively. Improvement was also reported for the SDAI, DAS28 CRP and HAQ, with scores consistently decreasing through Week 8. In the extension phase, 70.8%, 47.2% and 13.2% subjects achieved ACR20, -50 and -70 responses at Week 56. Improvement was also reported for the SDAI, DAS28 CRP and HAQ, with scores consistently decreasing through Week 56.

From Baseline through Week 8 the mean serum concentrations of investigational AVT02 increased consistently at each visit, reaching a peak at Week 24. There was no significant difference in serum concentrations of AVT02 based on injection subsite (abdomen or thigh).

ADAs were detected in 65.1% of subjects through Week 8, reducing to 49.1% by Week 56. Of ADA-positive subjects, most were also positive for neutralizing antibodies through Week 8 (62.3%) increasing through Week 56 (90.4%). Subjects who were ADA-positive had lower serum concentrations of study drug compared with the overall population at Week 8 and Week 56 as expected.

There were no clinically relevant safety or tolerability issues. Overall, treatment-emergent adverse events reported in at least 5% of subjects at the PT level were anaemia and influenza (6 subjects [5.6%)] reported 6 events each), and no local ISRs were reported.

Conclusion

The fully successful self-injection with the AI in this study supported the use of the device while administering AVT02. Furthermore, subjects typically found the AI easy to use, with ease of use increasing as time progressed.

The ACR20, -50, and -70, SDAI, DAS28 CRP and HAQ results supported the use of AVT02 to treat adult patients with moderate-to-severe RA, with the treatment effect persisting beyond Week 8 and through Week 56.

The safety and immunogenicity profiles were as expected for adalimumab.

ClinicalTrials.gov Identifier: NCT04224194

Disclosure of Interests

Nemanja Damjanov: None declared, Heimo Stroissnig Employee of: Alvotech, Matjaz Steiger Employee of: Alvotech, Joanna Sobierska Employee of: Alvotech, Eric Guenzi Employee of: Alvotech, Hendrik Otto Employee of: Alvotech, Abid Sattar Employee of: Alvotech, Halimu N. Haliduola Employee of: Alvotech, Elin Edwald Employee of: Alvotech, Fausto Berti Employee of: Alvotech

Morphological and molecular evidences of Ascaridia galli in migratory quail Coturnix coturnix japonica from Baluchistan Pakistan

Abstract The current study was conducted to examine the point prevalence of gastrointestinal parasites of migratory quails. Due to its economic importance, the control of ascaridiosis is critical. Migration of birds is considered to enhance the global spread and cross-species transmission of pathogens. The current study was aimed to detect A.galli in migratory quails, a potential contributory risk factor for transmission of this parasite to local birds. A total of 230 migratory quails were trapped using nets from migratory routes in Balochistan and examined under the compound microscope for the presence of A. galli. Conventionally, A. galli was identified by its morphology with the presence of three large lips and absence of posterior esophageal bulb. Results revealed that out of 230, 120 (52.17%) quails were positive for A. galli by targeting COX1 gene (533 bp) by using conventional PCR. Further, the amplicon was sequenced which showed 99% similarity with A. galli publically available in NCBI Gen Bank. Phylogenetic analysis of sequences of our isolated parasite indicated the close relationship with A.galli isolated from chickens. In conclusion migratory quails and other migratory birds may play a key role in spreading and transmission of these parasites and other pathogens to domestic chicken. Therefore, strict biosecurity measures should be adopted especially for commercial poultry farms.

Prematurity and postnatal alterations in intermittent hypoxaemia

Intermittent hypoxaemia (IH) events are well described in extremely preterm infants, but the occurrence of IH patterns in more mature preterm infants remains unclear. The objective of this study was to characterise the effect of gestational age on early postnatal patterns of IH in extremely (<28 weeks), very (28-<32 weeks) and moderately (32-<34 weeks) preterm infants. As expected, extremely preterm infants had a significantly higher frequency of IH events of longer durations and greater time with hypoxaemia versus very and moderately preterm infants. In addition, the postnatal decrease in IH duration was comparable in the very and moderately preterm infants. This progression of IH events should assist clinicians and families in managing expectations for resolution of IH events during early postnatal life.

A massive rock and ice avalanche caused the 2021 disaster at Chamoli, Indian Himalaya

On 7 February 2021, a catastrophic mass flow descended the Ronti Gad, Rishiganga, and Dhauliganga valleys in Chamoli, Uttarakhand, India, causing widespread devastation and severely damaging two hydropower projects. More than 200 people were killed or are missing. Our analysis of satellite imagery, seismic records, numerical model results, and eyewitness videos reveals that ~27 × 10⁶ cubic meters of rock and glacier ice collapsed from the steep north face of Ronti Peak. The rock and ice avalanche rapidly transformed into an extraordinarily large and mobile debris flow that transported boulders greater than 20 meters in diameter and scoured the valley walls up to 220 meters above the valley floor. The intersection of the hazard cascade with downvalley infrastructure resulted in a disaster, which highlights key questions about adequate monitoring and sustainable development in the Himalaya as well as other remote, high-mountain environments.

Evaluation of synchronization protocols and methods of early pregnancy diagnosis in dairy cattle

The studies aimed to evaluate the pregnancy rate (PR) for timed artificial insemination (TAI) after G7G-Ovsynch, modified G7G-Ovsynch (MG7G-Ovsynch) and Ovsynch protocols and to assess the accuracy of using pregnancy-associated glycoproteins (PAGs) and plasma progesterone (P4) in pregnancy diagnosis compared with ultrasonography (US). In study 1, Holstein cows (n = 37) were bred by TAI following the G7G-Ovsynch protocol (n = 19) or MG7G-Ovsynch (n = 18). Pregnancy was evaluated by US at days 31, 59, and 87 after breeding. The PR was not different for the G7G-Ovsynch and MG7G-Ovsynch. Blood and milk samples were collected on day 3 after insemination and then weekly through day 59 post TAI in cows diagnosed as not pregnant on day 31 and through day 87 in pregnant cows. PAGs were measured using ELISA and P4 by radioimmunoassay (RIA). In the second study, Holstein cows (n = 212) were bred by TAI following G7G-Ovsynch protocol (n = 110) or standard Ovsynch (n = 102). Cows were subjected to pregnancy diagnosis on days 30, 60, and 90. A subset (n = 15 in each group) was subjected to blood and milk samples on days 30, 45, 60, 75, and 90 to measure PAGs and P4. In study 2, PR was not significantly different between synchronization protocols on days 30, 60, and 90. Pregnancy loss averaged 15% between day 30 and day 90. The use of PAGs and P4 proved equally effective in diagnosis of pregnancy. Thus, G7G-Ovsynch was deemed the protocol of choice in postpartum cows, and PAGs assayed in milk or plasma could be used to diagnose pregnancy.

Insulin resistance and intestinal integrity in children with and without HIV infection in Uganda

OBJECTIVES

The risk of cardiometabolic complications in children with perinatally acquired HIV infection (PHIVs) and in perinatally HIV-exposed but uninfected children (HEUs) and its relationship to systemic inflammation and markers of gut integrity are not well established. In this current study, we assed insulin resitance in PHIV compared to HEUs and HIV unexposed uninfected children and explored potential association with intestinal damage biomarkers.

METHODS

This was a cross-sectional study in PHIVs, HEUs and HIV-unexposed, uninfected children (HUUs) aged 2-10 years enrolled in Uganda. PHIVs were on stable antiretroviral therapy (ART) with HIV viral load  < 400 HIV-1 RNA copies/mL. Insulin resistance was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR). We measured markers of systemic inflammation, monocyte activation and gut integrity. Kruskal-Wallis tests were used to compare markers by HIV status; Pearson correlation and multiple linear regressions were used to assess associations of the HOMA-IR index with biomarkers of intestinal damage and translocation.

RESULTS

Overall, 172 participants were enrolled in the study (57 PHIVs, 59 HEUs and 56 HUUs). The median age was 7.8 [interquartile range (IQR) 6.39, 8.84] years, 55% were female and the median body mass index (BMI) was 15 (IQR 14.3, 15.8) kg/m² . Among PHIVs, the median CD4% was 37%, and 93% had viral load ≤ 20 copies/mL. PHIVs had higher waist:hip ratio, high-density lipoprotein (HDL) cholesterol, triglycerides and HOMA-IR index than the other groups (P ≤ 0.02). Factors correlated with insulin resistance included higher BMI and HDL cholesterol and lower soluble tumour necrosis factor receptor I (sTNFRI) (P ≤ 0.02). There was no correlation between any of the other inflammatory or gut biomarkers and HOMA-IR index (P ≥ 0.05). After adjusting for age and sTNFRI, BMI remained independently associated with the HOMA-IR index (β = 0.16; P < 0.01).

CONCLUSIONS

Despite viral suppression, Ugandan PHIVs have disturbances in glucose metabolism. Higher BMI, and not immune activation or alteration of gut integrity, was associated with insulin resistance in this population.

Alcohol and dietary factors associate with gut integrity and inflammation in HIV-infected adults

OBJECTIVES

HIV-infected adults have heightened monocyte activation and inflammation, at least partially as a consequence of altered gut integrity. The role of dietary factors in microbial translocation and inflammation and their downstream effect on markers of cardiovascular disease (CVD) have not been explored. Our purpose was to describe the longitudinal dietary patterns of HIV-infected adults, and to examine the relationship between dietary intake, gut integrity, inflammation and subclinical markers of CVD in HIV-infected adults.

METHODS

We conducted a secondary analysis of 147 HIV-infected participants in a 96-week randomized clinical trial of rosuvastatin as primary CVD prevention. Dietary intake was assessed using dietary recall; plasma gut integrity, monocyte activation and inflammation markers were measured using an enzyme-linked immunosorbent assay (ELISA); and CVD risk was assessed using carotid ultrasound and the coronary artery calcium score. Linear mixed models were used to analyse longitudinally measured biomarkers.

RESULTS

The median age was 45 years and 78% of patients were male. At baseline, participants consumed a mean (standard deviation) of 108 (70) g of fat daily, 19 (15.6) g of fibre, 266 (186) g of carbohydrates and 15.6 (5.9) g of protein; 45% of the sample consumed alcohol. Over time, alcohol consumption was associated with several markers of gut integrity and inflammation (all P < 0.05).

CONCLUSIONS

HIV-infected adults in a contemporary, high-resource setting have poor dietary patterns. Alcohol use was associated with worse gut integrity and increased inflammation, while other aspects of diet (fibre, carbohydrates and fat) were not. These data add to growing evidence illustrating the need for a better understanding of the effect of lifestyle factors on comorbidities in HIV-infected adults.

Comparison of transvaginal and transabdominal ultrasonography in the diagnosis of ectopic pregnancy

This cross sectional study was carried out in the department of Radiology and Imaging, Dhaka Medical College Hospital from July 2008 to June 2010 to compare the accuracy of transvaginal ultrasonography and transabdominal ultrasonography in the diagnosis of clinically suspected cases of ectopic pregnancy. Initially 60 patients with clinical suspicion of ectopic pregnancy were included in this study after analyzing selection criteria 30 patients underwent both transvaginal and transabdominal ultrasonography. 'Histopathological diagnosis' was considered gold standard against which accuracies of two diagnostic modalities were compared. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of transabdominal ultrasonography as a diagnostic modality in evaluation of suspected ectopic pregnancy were 73.1%, 75%, 95%, 30% and 73.3% respectively where as transvaginal ultrasonography was found to have 92.3% sensitivity, 75% specificity, 96% positive predictive value, 60% negative predictive value and 90% accuracy. Transvaginal ultrasonography was superior to transabdominal ultrasonography in the evaluation of suspected ectopic pregnancies so, transvaginal ultrasonography is important for early and accurate diagnosis of ectopic pregnancy.

NuMVC: An Efficient Local Search Algorithm for Minimum Vertex Cover

The Minimum Vertex Cover (MVC) problem is a prominent NP-hard combinatorial optimization problem of great importance in both theory and application. Local search has proved successful for this problem. However, there are two main drawbacks in state-of-the-art MVC local search algorithms. First, they select a pair of vertices to exchange simultaneously, which is time-consuming. Secondly, although using edge weighting techniques to diversify the search, these algorithms lack mechanisms for decreasing the weights. To address these issues, we propose two new strategies: two-stage exchange and edge weighting with forgetting. The two-stage exchange strategy selects two vertices to exchange separately and performs the exchange in two stages. The strategy of edge weighting with forgetting not only increases weights of uncovered edges, but also decreases some weights for each edge periodically. These two strategies are used in designing a new MVC local search algorithm, which is referred to as NuMVC. We conduct extensive experimental studies on the standard benchmarks, namely DIMACS and BHOSLIB. The experiment comparing NuMVC with state-of-the-art heuristic algorithms show that NuMVC is at least competitive with the nearest competitor namely PLS on the DIMACS benchmark, and clearly dominates all competitors on the BHOSLIB benchmark. Also, experimental results indicate that NuMVC finds an optimal solution much faster than the current best exact algorithm for Maximum Clique on random instances as well as some structured ones. Moreover, we study the effectiveness of the two strategies and the run-time behaviour through experimental analysis.

Extending Dual Arc Consistency

Many extensions to existing binary constraint satisfaction algorithms have been proposed that directly deal with nonbinary constraints. Another choice is to perform a structural transformation of the representation of the problem, so that the resulting problem is a binary CSP except that now the original constraints which were nonbinary are replaced by binary compatibility constraints between relations. A lot of recent work has focussed on comparing different levels of local consistency enforceable in the nonbinary representation with the dual representation. In this paper we present extensions to the standard dual encoding that can compactly represent the given CSP using an equivalent dual encoding that contains all the original solutions to the CSP, using constraint coverings. We show how enforcing arc consistency in these constraint covering based encodings, strictly dominates enforcement of generalized arc consistency (GAC) on the primal nonbinary encoding.

The influence of gamete co-incubation length on the in vitro fertility and sex ratio of bovine bulls with different penetration speed

The objectives of this work were to evaluate whether the sperm penetration speed is correlated to the in vitro fertility and whether adapting the gamete co-incubation length to the kinetics of the bull improves in vitro fertility and affects the sex ratio. In vitro matured oocytes were co-incubated with spermatozoa from four different bulls (A-D). At various post-insemination (p.i.) times (4, 8, 12, 16 and 20 h), samples of oocytes were fixed and stained with DAPI for nuclei examination, while the remaining ones were transferred into culture to evaluate embryo development. The blastocysts produced were sexed by PCR. Two bulls (A and B) had faster kinetics than the others (C and D), as shown by the higher penetration rates recorded at 4 h p.i. (43%, 30%, 11% and 6%, respectively for bulls A, B, C and D; p<0.01). The differences in the kinetics among bulls did not reflect their in vitro fertility. The incidence of polyspermy was higher for faster penetrating bulls (36%, 24%, 16% and 4%, respectively for bulls A, B, C and D; p<0.01) and at longer co-incubation times (0%, 16%, 19%, 30% and 34%, respectively at 4, 8, 12, 16 and 20 h p.i.; p<0.01). The fertilizing ability of individual bulls may be improved by adapting the co-incubation length to their penetration speed. A sperm-oocyte co-incubation length of 8 h ensured the greatest blastocyst yields for the two faster penetrating bulls. On the contrary, 16 h co-incubation was required to increase (p<0.01) cleavage rate of the two slower bulls. Bulls with a faster kinetics did not alter the embryo sex ratio towards males. The female/male (F/M) ratios recorded were 2.1, 1.4, 1.2, 1.3 and 1.6, respectively at 4, 8, 12, 16 and 20 h p.i.

311 MELATONIN PROMOTES IN VITRO SPERM CAPACITATION IN BUFFALO (BUBALUS BUBALIS)

Melatonin, the main hormone secreted by the pineal gland, plays many roles in reproduction. In ram spermatozoa, melatonin administration increases plasminogen activator activity (Tsantarliotou MP et al. 2007 Theriogenology 69, 458-465), known to be involved in sperm capacitation and acrosome reaction (Taitzoglou IA et al. 1996 Mol. Androl. 8, 187-197). The aim of this study was to evaluate the efficiency of melatonin to induce buffalo in vitro sperm capacitation, indirectly assessed by estimating the capability of spermatozoa to acrosome-react. Frozen-thawed semen from 4 different bulls was pooled and treated by swim-up in order to select only the motile population. Spermatozoa (n = 829) were assessed immediately after swim- up separation, to evaluate the incidence of acrosomal loss in non-treated cells (time 0). The remaining spermatozoa were incubated in the absence of capacitating agents (negative control; n = 513), in the presence of 0.01 mM heparin (positive control; n = 775), 10 μM melatonin (n = 684), 100 μM melatonin (n = 751), and 1 mM melatonin (n = 650), for 2 h. Sperm were then exposed for 15 min to 60 μg mL-1 of lysophosphatidylcholine, an agent known to induce acrosome reaction (AR) only on capacitated spermatozoa. Trypan blue was used first to differentiate live from dead spermatozoa and the dried smears were then fixed in 37% formaldehyde and stained with Giemsa for acrosome evaluation by microscopic examination. The percentage of acrosome-reacted spermatozoa in each group was used to assess the efficiency of capacitation under different incubation conditions. The experiment was repeated 4 times. Differences among groups were analyzed by chi-square test. Acrosomal loss was observed only in 2.1% of the sperm population at time 0. Interestingly, sperm treatment with both heparin and the different concentrations of melatonin resulted in a significantly higher incidence of AR compared to the negative control (24.4, 20.5, 20.0, 23.6 v. 8.0% for the positive control, 10 μM melatonin, 100 μM melatonin, 1 mM melatonin, and the negative control, respectively; P < 0.01). These results demonstrated that melatonin determines capacitation of buffalo spermatozoa in vitro. Furthermore, the effect of melatonin was comparable to that of heparin, that is, the capacitating agent currently used in the IVF system. The capacitating effect was observed at all the tested concentrations, and viability was not affected. This suggests to extend the range of concentrations to test in future studies, in order to identify the optimal dose. Moreover, considering the seasonality of the species and the great differences in fertility attitude of buffalo bulls, it would be interesting to investigate the capacitation effect of melatonin in relation to both the season and the bull.

322 EFFECT OF PLASMIN ON ACROSOME REACTION OF BUFFALO (BUBALUS BUBALIS) SPERMATOZOA IN VITRO

Fertilization is a critical step of the in vitro embryo production (IVEP) technology in buffalo. It is known that proteolytic enzymes are involved in different steps of the fertilization process; among these, a critical role may be played by the plasminogen activator-plasmin system. It has been demonstrated that plasmin, the active enzyme of this system, induces acrosome reaction (AR) in bull spermatozoa (Taitzoglou IA et al. 2003 Andrologia 35, 112-116). The aim of this study was to investigate the effect of plasmin on the ability of buffalo sperm to undergo the AR. Frozen- thawed sperm from 4 buffalo bulls were treated by swim-up and incubated with 0.01 mM heparin for 4 h. At 0, 2, and 4 h, aliquots of spermatozoa were exposed for 10 min to 60 μg mL-1 of lysophosphatidylcholine (LPC), as positive control, and to 0.01 μg mL-1 of plasmin. This concentration was chosen after a preliminary dose-response trial. Another sample from each treatment was incubated with IVF medium (negative control). After 10 min, sperm motility was evaluated and sperm were fixed in 37% formaldehyde and stained with trypan blue-Giemsa for subsequent microscopic examination. The total number of sperm counted, over 3 replicates, was 1269 for the negative control, 1293 for LPC, and 1238 for plasmin, equally distributed among incubation times. Differences among groups were analyzed by chi-square test. After swim-up, acrosomal loss was observed only in 4% of the sperm. The addition of 0.01 μg mL-1 of plasmin for 10 min to buffalo spermatozoa at time 0 significantly (P < 0.01) enhanced (23%) AR compared with the control (7.8%), with the same efficiency of LPC (17.1%). After 2 h of incubation with heparin, both plasmin and LPC increased the AR compared to the control (24.4, 20.1, and 14.0%, respectively; P < 0.01). After 4 h, plasmin gave higher percentages of AR (27.2%) compared to both the control (21.0%; P < 0.05) and LPC (19.2%; P < 0.01). Another interesting result is the improved motility recorded with plasmin compared to both the control and LPC groups at 2 h of incubation (90, 75, and 75%, respectively; P < 0.05) and at 4 h of incubation (75, 60, and 60%, respectively; P < 0.05). Finally, no differences in sperm viability were observed between plasmin and the control, whereas a decreased viability was found when LPC was used at 0 h (96.2, 95.0, and 89.0%, respectively, for plasmin, control, and LPC; P < 0.05), at 2 h (85.0, 87.5, and 77.0%, respectively, for plasmin, control, and LPC; P < 0.01), and at 4 h (85.0, 93.3, and 81.1%, respectively, for plasmin, control, and LPC; P < 0.01). In conclusion, we found that addition of plasmin to capacitated sperm increases the percentage of acrosome-reacted spermatozoa and improves motility. Our results suggest that plasmin may play a role in events surrounding fertilization and suggest to evaluate in further studies whether the addition of plasmin during IVF improves the IVEP efficiency in buffalo.

Variable Forgetting in Reasoning about Knowledge

In this paper, we investigate knowledge reasoning within a simple framework called knowledge structure. We use variable forgetting as a basic operation for one agent to reason about its own or other agents\' knowledge. In our framework, two notions namely agents\' observable variables and the weakest sufficient condition play important roles in knowledge reasoning. Given a background knowledge base and a set of observable variables for each agent, we show that the notion of an agent knowing a formula can be defined as a weakest sufficient condition of the formula under background knowledge base. Moreover, we show how to capture the notion of common knowledge by using a generalized notion of weakest sufficient condition. Also, we show that public announcement operator can be conveniently dealt with via our notion of knowledge structure. Further, we explore the computational complexity of the problem whether an epistemic formula is realized in a knowledge structure. In the general case, this problem is PSPACE-hard; however, for some interesting subcases, it can be reduced to co-NP. Finally, we discuss possible applications of our framework in some interesting domains such as the automated analysis of the well-known muddy children puzzle and the verification of the revised Needham-Schroeder protocol. We believe that there are many scenarios where the natural presentation of the available information about knowledge is under the form of a knowledge structure. What makes it valuable compared with the corresponding multi-agent S5 Kripke structure is that it can be much more succinct.

Lipoprotein (a) and glycaemic control in Pakistani subjects with diabetes mellitus

AIMS

To measure lipoprotein (Lp)(a) levels in people with diabetes mellitus (DM) and to see if there is any difference in Lp(a) levels between diabetics with good glycaemic control and those with poor glycaemic control.

METHODS

Sixty subjects with DM and thirty healthy individuals were studied. Fasting blood samples were analyzed for glucose, glycosylated hemoglobin, Serum total cholesterol, triglycerides, low density lipoproteins, high density lipoproteins and Lp(a).

RESULTS

A non significant difference was found between the lipid profile of normal individuals and subjects with DM with a good glycemic control. Lp(a) levels were significantly raised in diabetics. The difference in Lp(a) levels between well controlled and poorly controlled diabetics was non significant. In the control group 23.4% of individuals had high risk levels of Lp(a) while it was 46.7 % for people with DM.

CONCLUSION

Glycaemic control improves lipid profile positively in diabetics and may even lead to near normalization of lipoprotein concentrations. Diabetics have elevated levels of Lp(a) and the difference in Lp(a) levels between well controlled and poorly controlled diabeticsts is non-significant.

FBG and TC/HDL ratios in type 2 diabetes mellitus

BACKGROUND

Presence of dyslipidemia, i.e. raised Total Cholesterol (TC) and decreased High Density Lipoproteins (HDL) is an established phenomenon in type 2 diabetes mellitus. Its relationship to the fasting blood sugar (FBG) level in both diabetics and non-diabetics has yet to be established. The present study aims to show such a relationship.

METHODS

150 subjects were selected and divided into two groups, one of 50 controls (non-diabetics), the other of 100 patients with type 2 diabetes mellitus. Their FBG levels were determined by enzyme oxidase method, and their TC and HDL levels were determined using a standard kit method.

RESULTS

FBG and TC:HDL ratios were increased in the patient group (p = < 0.001). Comparison of FBG and TC:HDL ratios revealed a highly significant rise (p = < 0.001) in the patient group. FBG with TC:HDL ratios between both groups showed a positive correlation (r = 0.554).

CONCLUSION

The results of the present study suggest an association between FBG and TC:HDL ratios, which may be a contributory factor to the increased prevalence of coronary artery disease in patients with type 2 diabetes mellitus.

Phenolics and physico-chemical characteristics of persimmon during post-harvest storage

Garden picked mature but unripe fresh persimmon fruits were unipackaged in different thicknesses of polyethylene (PE) and stored at room (18.5-30 degrees C) and refrigerated temperature (6 +/- 1 degrees C). Maximum mean methanol extractable sinapine (0.168%), catechin (1.51%), and leucoanthocyanidine (10.94 delta A550/g) were recorded in the unipackaged samples kept at room temperature during 6 weeks storage, whereas the minimum values for water extractable phenolics (sinapin, catechin and procyanidin) were recorded in unipackaged samples under refrigerated temperature. The mean maximum weight loss of 12.58 and 7.90% was recorded in control samples kept at room temperature and low temperature, respectively. The weight loss for unipackaged in different thicknesses of PE ranged between 0.93-0.96% and 0.43-0.45% for samples kept at room and low temperature, respectively. Changes in texture values were significantly faster in control than unipackaged samples (P < 0.05). Low temperature combined with unipackaging in PE film performed better for the maintenance of overall fruit quality during post-harvest storage.

Metabolic proficiency and benzo[a]pyrene DNA adduct formation in APCMin mouse adenomas and uninvolved mucosa

Tumour formation may involve interactions between genetic factors and environmental carcinogens. Adenoma formation in APCMin/+ mice is associated homozygous adenomatous polyposis coli (APC) gene mutation, but the effects on carcinogen susceptibility are unknown. This study tests the hypothesis that APCMin/+ adenoma formation is accompanied by changes in metabolic proficiency and carcinogen susceptibility. Cytochrome P450 (CYP)1A1/1A2, glutathione S-transferase (GST)alpha, mu and pi classes and DNA adduct formation were assayed in adenomas and uninvolved mucosa from APCMin/+ mice, before and after benzo[a]pyrene (B[a]P) treatment. In untreated adenomas and mucosa, CYP1A1/1A2 and B[a]P-DNA adducts were undetected but GSTalpha, mu and pi class enzymes were constitutively expressed. In adenomas, B[a]P only induced CYP1A1/1A2 to low level while GSTalpha and pi class enzymes were unaffected. A GST mu band which was absent from mucosa, was induced in adenomas. In mucosa, B[a]P induced CYP1A1/1A2 and GSTalpha and pi, to high levels. B[a]P-DNA adduct levels were 56 +/- 15/10(8) nucleotides (median +/- SE) in adenomas versus 89 +/- 19/10(8) nucleotides in mucosa (P < 0.0001). APCMin adenomas show reduced bioactivation capacity and sustain less DNA damage from B[a]P exposure, than APCMin uninvolved mucosa. These properties could influence mutagenesis and subsequent neoplastic transformation of adenomas.

Concurrent treatment of patients with depression in the community: provider practices, attitudes, and barriers to collaboration

BACKGROUND

In randomized controlled trials, patients with major depression who receive broad-based collaborative treatment by both primary care physicians (PCPs) and mental health providers (MHPs) have better outcomes than patients who receive usual care. However, little is known about the concurrent treatment of patients with depression in the community. This study describes the perceptions of PCPs of the frequency of concurrent treatment in community settings, the degree of collaboration between co-treating providers, and factors associated with greater interaction and collaboration.

METHODS

A survey was distributed to a stratified, random sample of 276 eligible family physicians in Michigan. Primary analyses were descriptive statistics (point estimation) of PCP practice patterns. Secondary analyses explored predictors of collaboration with multivariable regression.

RESULTS

A total of 162 eligible PCPs (59%) returned the survey. PCPs reported that they co-treated approximately 30% of their depressed patients with MHPs. They made contact with co-treating MHPs in approximately 50% of shared cases; however, provider contact seldom included joint treatment planning. PCPs perceived collaborative treatments to be more problematic when patients were enrolled in managed care programs. In multivariable regression, co-location of MHP and PCP practices (in the same building) was strongly associated with increased interaction and collaboration (P <.001).

CONCLUSIONS

Concurrent treatment of depressed patients is common in the community, but these treatments are less interactive and collaborative than the treatment models proven effective in randomized controlled trails. If concurrent treatments are to become more collaborative-with regular contact and effective communication-co-location of practices appears important.

Expression of growth regulatory genes in a SCID mouse-human model of intestinal epithelial regeneration

Analysis of human intestinal epithelial regeneration has been limited. This study has used a novel SCID mouse-human model to test the hypothesis that distinct stages of human intestinal epithelial regeneration are accompanied by differential expression of growth regulatory genes. Disaggregated epithelium, which included crypt cell aggregates, was isolated from human fetal small intestine and transplanted subcutaneously in SCID mice. This method induced a coordinated regeneration response and enabled temporal separation of cell populations at different stages of histogenesis and cytodifferentiation. Graft epithelium was identified using a specific anti-human monoclonal antibody (MAb 5D3) against cytokeratins 8 and 18. Functional epithelial lineages were identified by appropriate markers. Growth regulatory genes relevant to proliferation and apoptosis, including Bcl-2, p53 and Ki67, were assayed at different stages of regeneration. During early regeneration, Bcl-2, p53, and Ki67 were expressed throughout the epithelial compartment. On completion of regeneration, these genes were expressed only in crypt epithelium and were absent from villi. This study has established a novel SCID mouse-human model of intestinal epithelial regeneration. During early regeneration, increased Bcl-2 and Ki67 expression may indicate suppression of apoptosis and enhanced proliferation respectively, consistent with expansion of the stem cell fraction. The p53 gene may influence pathways of differentiation during regeneration, analogous to its role during development.