HSF1 Pathway Inhibitor Clinical Candidate (CCT361814/NXP800) Developed from a Phenotypic Screen as a Potential Treatment for Refractory Ovarian Cancer and Other Malignancies

CCT251236 1, a potent chemical probe, was previously developed from a cell-based phenotypic high-throughput screen (HTS) to discover inhibitors of transcription mediated by HSF1, a transcription factor that supports malignancy. Owing to its activity against models of refractory human ovarian cancer, 1 was progressed into lead optimization. The reduction of P-glycoprotein efflux became a focus of early compound optimization; central ring halogen substitution was demonstrated by matched molecular pair analysis to be an effective strategy to mitigate this liability. Further multiparameter optimization led to the design of the clinical candidate, CCT361814/NXP800 22, a potent and orally bioavailable fluorobisamide, which caused tumor regression in a human ovarian adenocarcinoma xenograft model with on-pathway biomarker modulation and a clean in vitro safety profile. Following its favorable dose prediction to human, 22 has now progressed to phase 1 clinical trial as a potential future treatment for refractory ovarian cancer and other malignancies.

Colistin kills bacteria by targeting lipopolysaccharide in the cytoplasmic membrane

Colistin is an antibiotic of last resort, but has poor efficacy and resistance is a growing problem. Whilst it is well established that colistin disrupts the bacterial outer membrane (OM) by selectively targeting lipopolysaccharide (LPS), it was unclear how this led to bacterial killing. We discovered that MCR-1 mediated colistin resistance in Escherichia coli is due to modified LPS at the cytoplasmic rather than OM. In doing so, we also demonstrated that colistin exerts bactericidal activity by targeting LPS in the cytoplasmic membrane (CM). We then exploited this information to devise a new therapeutic approach. Using the LPS transport inhibitor murepavadin, we were able to cause LPS accumulation in the CM of Pseudomonas aeruginosa, which resulted in increased susceptibility to colistin in vitro and improved treatment efficacy in vivo. These findings reveal new insight into the mechanism by which colistin kills bacteria, providing the foundations for novel approaches to enhance therapeutic outcomes.

Identification of a potent small-molecule inhibitor of bacterial DNA repair that potentiates quinolone antibiotic activity in methicillin-resistant Staphylococcus aureus

The global emergence of antibiotic resistance is one of the most serious challenges facing modern medicine. There is an urgent need for validation of new drug targets and the development of small molecules with novel mechanisms of action. We therefore sought to inhibit bacterial DNA repair mediated by the AddAB/RecBCD protein complexes as a means to sensitize bacteria to DNA damage caused by the host immune system or quinolone antibiotics. A rational, hypothesis-driven compound optimization identified IMP-1700 as a cell-active, nanomolar potency compound. IMP-1700 sensitized multidrug-resistant Staphylococcus aureus to the fluoroquinolone antibiotic ciprofloxacin, where resistance results from a point mutation in the fluoroquinolone target, DNA gyrase. Cellular reporter assays indicated IMP-1700 inhibited the bacterial SOS-response to DNA damage, and compound-functionalized Sepharose successfully pulled-down the AddAB repair complex. This work provides validation of bacterial DNA repair as a novel therapeutic target and delivers IMP-1700 as a tool molecule and starting point for therapeutic development to address the pressing challenge of antibiotic resistance.

Exploitation of Antibiotic Resistance as a Novel Drug Target: Development of a β-Lactamase-Activated Antibacterial Prodrug

Expression of β-lactamase is the single most prevalent determinant of antibiotic resistance, rendering bacteria resistant to β-lactam antibiotics. In this article, we describe the development of an antibiotic prodrug that combines ciprofloxacin with a β-lactamase-cleavable motif. The prodrug is only bactericidal after activation by β-lactamase. Bactericidal activity comparable to ciprofloxacin is demonstrated against clinically relevant E. coli isolates expressing diverse β-lactamases; bactericidal activity was not observed in strains without β-lactamase. These findings demonstrate that it is possible to exploit antibiotic resistance to selectively target β-lactamase-producing bacteria using our prodrug approach, without adversely affecting bacteria that do not produce β-lactamase. This paves the way for selective targeting of drug-resistant pathogens without disrupting or selecting for resistance within the microbiota, reducing the rate of secondary infections and subsequent antibiotic use.

Privileged Structures and Polypharmacology within and between Protein Families

Polypharmacology is often a key contributor to the efficacy of a drug, but is also a potential risk. We investigated two hits discovered via a cell-based phenotypic screen, the CDK9 inhibitor CCT250006 (1) and the pirin ligand CCT245232 (2), to establish methodology to elucidate their secondary protein targets. Using computational pocket-based analysis, we discovered intrafamily polypharmacology for our kinase inhibitor, despite little overall sequence identity. The interfamily polypharmacology of 2 with B-Raf was used to discover a novel pirin ligand from a very small but privileged compound library despite no apparent ligand or binding site similarity. Our data demonstrates that in areas of drug discovery where intrafamily polypharmacology is often an issue, ligand dissimilarity cannot necessarily be used to assume different off-target profiles and that understanding interfamily polypharmacology will be important in the future to reduce the risk of idiopathic toxicity and in the design of screening libraries.

Targeting secondary protein complexes in drug discovery: studying the druggability and chemical biology of the HSP70/BAG1 complex

A non-nucleotide FP-probe was designed to study the mechanism of action and druggability of the secondary HSP70/BAG1 complex.

Proteins typically carry out their biological functions as multi-protein complexes, which can significantly affect the affinity of small-molecule inhibitors. HSP70 is an important target in oncology, so to study its chemical biology and the drug discovery potential of the HSP70/BAG1 complex, we designed a high-affinity non-nucleotide fluorescence polarisation probe.

Abstract LB-304: Discovery of chemical probe CCT251236: An orally bioavailable efficacious pirin ligand from an HSF1 phenotypic screen

Heat shock factor 1 (HSF1) was originally identified as a master regulator of the classical ‘cytoprotective’ heat shock response. However, a large body of evidence has now verified the importance of HSF1 to tumorigenesis and cancer progression. HSF1 is activated by various elements of the cancer state, reprogramming the transcriptome in a way that is overlapping with, but distinct from, the canonical heat-shock response. Also, there is a strong correlation between the expression of activated HSF1 in tumors and adverse clinical outcomes. This evidence indicates that the inhibition of HSF1-mediated transcription could be a viable strategy in cancer treatment. Inhibiting the HSF1 stress pathway represents an attempt at targeting non-oncogene addiction and proteotoxic stress, which has been proposed to be advantageous. However, HSF1 is a ligandless transcription factor and is unlikely to be amenable to standard drug discovery strategies and direct inhibition with small molecules. Therefore, we proposed that inhibitors of HSF1-mediated transcription, which antagonize the HSF1 pathway but without necessarily binding directly to HSF1, could be discovered and developed via a cell-based phenotypic screen. We carried out a high throughput Arrayscan assay of 200,000 compounds to measure the inhibition of HSF1-mediated HSP72 expression stimulated by pre-treatment with an HSP90 inhibitor. We identified a singleton hit with a bisamide core, CCT245232. This compound showed potent growth inhibition in a range of human cancer cell lines but had poor physicochemical properties leading to an unacceptable pharmacokinetic profile. Improvement of the physicochemical properties of CCT245232 whilst maintaining potency versus our cell-based assays led to the orally bioavailable tool compound CCT251236. This compound shows potent growth inhibition (GI50 values in low nanomolar range) of human ovarian cancer cell lines in vitro and good efficacy against human ovarian cancer xenografts in nude mice in vivo. We applied chemo-proteomic strategies to identify the molecular target using a probe based on CCT251236 and discovered pirin as a high affinity molecular target. Binding of CCT251236 to recombinant pirin was confirmed in biophysical assays. CCT251236 recapitulates the reported anti-migratory phenotype for a pirin ligand although binding to pirin alone does not explain the cellular phenotype observed with our chemical tool. We are currently using CCT251236 as a chemical probe while further optimizing its properties to identify a clinical candidate.

Citation Format: Matthew D. Cheeseman, Nicola E. Chessum, Carl S. Rye, Elisa A. Pasqua, Michael J. Tucker, Birgit Wilding, Lindsay E. Evans, Susan Lepri, Meirion Richards, Swee Y. Sharp, Salyha Ali, Martin Rowlands, Lisa O'Fee, Asadh Miah, Angela Hayes, Alan T. Henley, Marissa Powers, Robert te Poele, Emmanuel De Billy, Loredana Pellegrino, Florence Raynaud, Rosemary Burke, Robert L. van Montfort, Suzanne A. Eccles, Keith Jones, Paul Workman. Discovery of chemical probe CCT251236: An orally bioavailable efficacious pirin ligand from an HSF1 phenotypic screen [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-304. doi:10.1158/1538-7445.AM2017-LB-304

Discovery of a Chemical Probe Bisamide (CCT251236): An Orally Bioavailable Efficacious Pirin Ligand from a Heat Shock Transcription Factor 1 (HSF1) Phenotypic Screen

Phenotypic screens, which focus on measuring and quantifying discrete cellular changes rather than affinity for individual recombinant proteins, have recently attracted renewed interest as an efficient strategy for drug discovery. In this article, we describe the discovery of a new chemical probe, bisamide (CCT251236), identified using an unbiased phenotypic screen to detect inhibitors of the HSF1 stress pathway. The chemical probe is orally bioavailable and displays efficacy in a human ovarian carcinoma xenograft model. By developing cell-based SAR and using chemical proteomics, we identified pirin as a high affinity molecular target, which was confirmed by SPR and crystallography.

N-N bond-forming cyclization for the one-pot synthesis of N-aryl[3,4-d]pyrazolopyrimidines

An efficient one-pot synthesis of N-aryl[3,4-d]pyrazolopyrimidines in good yield and under mild reaction conditions is described. By exploiting electron-deficient hydroxylamines, the substituted oxime products were formed with very high E-diastereoselectivity. The key step utilizes a cyclization reaction upon an oxime derived from hydroxylamine-O-sulfonic acid to form the N–N bond of the product.

Glycolysis inhibitors negatively bias blood glucose measurements: potential impact on the reported prevalence of diabetes mellitus

BACKGROUND

Blood glucose concentrations are essential in defining diabetes mellitus. Recent guidelines advocate either of two discrete methods for sample collection and processing. One of these involves addition of glycolysis inhibitors, such as sodium fluoride-potassium oxalate (NaF-KOx) to sample collection tubes, whereas the other requires immediate refrigeration and sample separation.

AIMS

To examine whether the choice of the preanalytical process has any impact on subsequent glucose determinations.

METHODS

62 healthy men participated in the study during screening for diabetes. Paired venous blood samples were collected in a serum-gel tube and a tube containing NaF-KOx (both Sarstedt, Leicester, UK). Serum was promptly separated from gel tube samples and refrigerated, whereas NaF-KOx samples were not separated until immediately before analysis. Glucose concentrations were determined using an Olympus AU 2700 analyser incorporating an automated hexokinase method.

RESULTS

Mean (95% CI) glucose concentration in serum-gel tube samples was 5.2 mmol/l (5.0 to 5.4 mmol/l), whereas the concentration in tubes containing NaF-KOx was 4.9 mmol/l (4.8 to 5.1 mmol/l). A negative bias of 0.23 mmol/l (0.16 to 0.30 mmol/l) and relative negative bias of 4.7 % (3.2% to 6.3%) were observed for samples collected in NaF-KOx tubes, consistent with the combined effects of glycolysis and dilution.

CONCLUSIONS

Bias associated with the use of NaF-KOx tubes may have a significant impact on the prevalence of fasting hyperglycaemia, according to current diagnostic criteria. The small but significant difference between preanalytical processes should be considered when screening for the presence of diabetes mellitus.

Fatalities caused by the MDMA-related drug paramethoxyamphetamine (PMA)

The past several years have seen a marked increase in the recreational use of 3,4-methylenedioxymethamphetamine (MDMA) or "Ecstasy". MDMA use is especially common among young people participating in dance parties called "raves". Paramethoxyamphetamine (PMA) exhibits both structural and pharmacological similarity to MDMA. It may, however, be a more potent central stimulant, particularly in its effects on serotonergic transmission. Several fatalities from PMA have been reported in Australia, and here we report three recent fatalities that occurred in the midwestern United States in which each of the decedents believed that they were ingesting MDMA. Symptoms observed included agitation and bruxism, progressing to severe hyperthermia, convulsions, and hemorrhage. Blood was screened for drugs of abuse by enzyme immunoassay with the presence of amphetamines indicated in each case. Confirmation and quantitation for amphetamines was performed by gas chromatography-mass spectrometry. The deceased, two males ages 19 and 24 and a female age 18, had postmortem blood PMA concentrations of 1.07, 0.60, and 1.90 mg/L, respectively. PMA is not a contaminant of MDMA, and no MDMA was found in any of these cases. The primary metabolite of PMA is produced by O-demethylation to 4-hydroxyamphetamine, a reaction catalyzed by cytochrome P450 2D6. This enzyme is noted to be genetically polymorphic. Those with the "slow metabolizer" phenotype may be likely to have higher peak blood concentrations of PMA. Whether any of the decedents described herein were of the slow metabolizer phenotype is not known. Several groups have advocated the onsite use of the Marquis Test for the purpose of pill screening in efforts to distinguish PMA from MDMA. A dark purple is consistent with MDMA, whereas PMA imparts no color change in this test. PMA is often in the form of a white pill with a Mitsubishi symbol on one side. This design has been identified in at least one of these fatalities.

Clinical, bacteriologic, serologic, and pathologic features of infections with atypical Taylorella equigenitalis in mares

OBJECTIVE

To characterize clinical, serologic, bacteriologic, cytologic, and pathologic endometrial responses of mares to 2 donkey-origin atypical bacterial isolates resembling Taylorella equigenitalis.

DESIGN

Prospective in vivo study.

ANIMALS

10 healthy mares.

PROCEDURE

Mares in estrus (2/group) were inoculated by intrauterine infusion with 2 isolates of classic T equigenitalis or 2 isolates of atypical Taylorella sp or were sham-inoculated. Bacteriologic, serologic, clinical, uterine, cytologic, and pathologic endometrial responses were assessed 4, 11, 21, 35, and 63 days after inoculation and on day 111 in mares with positive culture results on day 63.

RESULTS

One atypical isolate failed to cause infection. The second atypical isolate and both classic T equigenitalis isolates induced similar transient metritis and cervicitis. Both classic isolates and 1 atypical isolate induced anti-T equigenitalis complement-fixing antibodies detectable at day 11. Classic isolates and an atypical isolate provoked intense neutrophilic endometritis followed by a resolving, subacute, neutrophilic-mononuclear endometrial response. The atypical isolate and classic isolates were recovered from the uterus, clitoral fossa, or clitoral sinus of one or both exposed mares for as long as 111 days.

CONCLUSIONS AND CLINICAL RELEVANCE

Atypical Taylorella sp infections should be considered as a differential diagnosis of equine infertility in US-origin mares, even those not exposed to stallions from countries where contagious equine metritis occurs. The origins and prevalence of atypical Taylorella sp infection in US horses and donkeys are undetermined.

A novel surgical technique for vasectomizing boars

A novel surgical technique was used for vasectomizing boars. The benefit of this approach over existing methods is that the ductus deferens is isolated prior to its entrance into the spermatic cord, thereby eliminating the potential for damage to associated neurovascular structures that are essential to testicular viability. Additionally, the described surgical procedure can be performed on boars positioned in lateral recumbency. Vasectomized boars can be used in breeding management strategies.

Removal of the caudae epididymides to create infertile boars for use in estrus detection programs

Epididymectomies (removal of the caudae epididymides) were performed to create infertile boars. The simplicity of this procedure allowed for it to be easily performed on physically or chemically restrained boars that weighted 30 kg. Benefits of the use of epididymectomy, rather than vasectomy, to render boars infertile include low cost, simplicity, reduced surgical time, and minimum need of surgical instruments and materials. Epididymectomized boars are used in swine breeding management programs.

A simple technique for the purification of plasma membranes from ejaculated boar spermatozoa

Spermatozoa were initially separated from fresh boar ejaculates using a 1.0 M sucrose density gradient. Spermatozoa (1 x 10(8) cells/ml) were subjected to gas cavitation (650 psi, 10 minutes), followed by a 4-step centrifugation technique to yield the final plasma membrane preparation. Purity of the plasma membrane isolate was determined using microscopic techniques (i.e. differential interference contrast and transmission electron microscopy) and marker enzymes for biochemical characterization. Plasma membranes were found to be removed primarily from the periacrosomal region of the sperm. Acrosomes appeared to remain intact on the cavitated spermatozoa. Transmission electron microscopy yielded a homogenous population of 100-200 microns unilamellar vesicles. Enzyme markers specific for plasma, acrosome and mitochondrial membranes substantial the purity observed under visual examination.

Excretion of porcine reproductive and respiratory syndrome virus in semen after experimentally induced infection in boars

Four boars intranasally inoculated with porcine reproductive and respiratory syndrome (PRRS) virus were monitored for 56 days after exposure for changes in semen characteristics and for the presence of virus in the semen. Clinically, 2 of 4 boars had mild respiratory signs of 1 day's duration after infection. Changes in appetite, behavior, or libido were not detected. All boars seroconverted on the indirect fluorescent antibody and serum virus neutralization tests by day 14 after inoculation. Virus was isolated from serum between days 7 and 14 after inoculation. During the monitoring period, semen volume decreased and pH correspondingly increased; however, this change began 7 to 10 days prior to infection. Differences in sperm morphologic features, concentration, or motility between the preinfection and postinfection samples were not observed. The PRRS virus was detected in semen at the first collection in each of the 4 boars (ie, 3 or 5 days after challenge exposure). Virus was detected in nearly all semen samples collected from the 4 infected boars through days 13, 25, 27, and 43, respectively. Neither gross nor microscopic lesions attributable to PRRS virus were observed in tissues collected at the termination of the experiment (day 56), and virus isolation results from reproductive tissues were negative.

Medically treated miscarriage in Alamance County, North Carolina, 1988-1991

The authors attempted to identify all medically treated miscarriages in Alamance County, North Carolina, between September 1988 and August 1991. Clinical and demographic characteristics of the cases were evaluated, and risks were calculated in relation to total pregnancies, including induced abortions. Miscarriage cases usually had positive pregnancy tests, and a sizable proportion (66% of whites, 72% of blacks) had a pathology report indicating the presence of a conceptus. Nineteen percent of the cases were identified in hospitals, a more common source for women who were unmarried, young, of low education, and had pregnancies of advanced gestational age. The risk of medically treated miscarriage was 7.7% among whites and 5.5% among blacks, with higher risks among older women. The lower risk among blacks, especially those with lower levels of education, suggests underascertainment, possibly resulting from a failure to seek treatment.

Transoral axial division, under endoscopic guidance, for correction of epiglottic entrapment in horses

Transoral axial division was performed, using endoscopic guidance, in 20 horses with epiglottic entrapment. Mean age of affected horses was 3 years (range, 2 to 5 years), and there were 18 Standardbreds and 2 Thoroughbreds. Standardbreds and female horses were significantly overrepresented when compared with a reference population. Upper respiratory noise prompted endoscopic examination before surgery in 16 horses, but noise was not heard in 4 horses. Ten horses had entrapment by thin tissue without ulceration, 6 horses had entrapment by thin tissue with small, partial-thickness ulceration, 3 horses had entrapment by moderately thick tissue with large, partial-thickness ulceration, and 1 horse had entrapment with thick tissue and severe ulceration. After surgery, horses received anti-inflammatory medication and box stall rest with hand walking for 7 days. All horses returned to race training on day 7 after surgery and returned to their previous level of racing or training. Epiglottic entrapment recurred in 2 horses (10%), and dorsal displacement of the palate developed in 2 horses after surgery. Relationship of epiglottic entrapment and dorsal displacement of the palate to epiglottic hypoplasia was not apparent. Transoral axial division under endoscopic guidance appeared to be a useful, safe, and economic alternative to currently available methods for management of epiglottic entrapment in horses. Horses with entrapment by thick and ulcerated tissue may be best managed by surgical resection of entrapping tissue.

Fetal dopamine cell survival after transplantation is dramatically improved at a critical donor gestational age in nonhuman primates

Mesencephalic tissue containing newly generated dopamine neurons was collected from brains of embryonic African green monkeys at 44 and 49 days of gestation and stereotaxically implanted into multiple sites in the caudate nucleus of adult monkeys previously treated with the dopamine protoxin, 1-methyl-4-phenyl-1,2,3,6-tetrathydropyridine. Ultrasonography was utilized to assess the developmental stage prior to hysterotomy. Brains were removed for combined histochemical and biochemical analyses at 3 1/2 months after grafting to determine the extent of graft survival and growth. The dopamine content of the target nucleus was assessed from microdissected "punches" placed in proximity to grafts identified in unfixed brain slices prior to fixation. Tissue dopamine levels adjacent to the grafts were elevated markedly, reaching 25-50% of control levels at some sites in the caudate nucleus. Morphometric analysis of graft size and dopamine cell numbers was performed with computer-enhanced, video-based imaging. Exceptionally large grafts that far exceeded their initial size at the time of implantation were seen at each placement site. The dopamine cell count was as high as 3500 in a single graft from E44 tissue, but only as high as 550 from the E49 donor. Up to 15,000 tyrosine hydroxylase-positive neurons were stained in the host monkey that received E44 tissue; only 1/10 as many were seen in each of the recipients of E49 day samples. The earlier donor grafts occupied as much as 15% of the caudate nucleus as seen in a single coronal section; summation of all sections that contained grafts at each placement from the E44 donor revealed average areas occupied by the grafts ranging from 3 to 8% of the caudate nucleus. In comparison, grafts produced from an E49 donor averaged between 2.4 and 5.4% of the area of the target. Qualitatively, grafts from each gestational stage showed well-developed dopamine neurons with morphological characteristics equivalent to those of all three ventral mesencephalic dopamine cell groups. The attainment of large, well-differentiated grafts with thousands of dopaminergic neurons from early gestation tissue suggests that optimal cell survival in primates is dependent on the degree of postgerminal development of the dopamine neuron. Neurite extension may be critical in this regard as well as other, at present, undefined factors. Maximal graft development and cell survival may be a critical element in the ability of neural grafts to reverse a neurological disability and to maintain improvement in the event of continued degeneration of host dopamine neurons.

Episodic scrotal mutilation with concurrent bilateral sperm granuloma in a dog

Bilateral sperm granuloma with diffuse spermatocele was found to be the cause of infertility in a young Golden Retriever. Anamnesis indicated that the dog had intermittent episodes of self-inflicted ulcerative scrotal dermatitis, beginning when it was 4 to 5 months old and regardless of season or environment. A complete breeding soundness examination produced consistently azoospermic ejaculates in the presence of bilaterally firm, distinct swellings of the epididymides. Because of the poor reproductive prognosis, the owner requested castration and scrotal ablation. Although scrotal trauma was initially thought to be associated with the onset of sperm granuloma formation, evaluation of the history and physical examination and laboratory findings indicated that a bilateral congenital anomaly was the most likely cause of infertility.

Surgical treatment of uterine torsion in a llama (Lama glama)

A multiparous llama was presented because of failure to proceed into the second stage of labor. Clockwise uterine torsion and a live fetus were identified by rectal and vaginal examinations. A cesarean operation was elected because of the prolonged first stage of labor and lack of cervical dilatation. Anesthesia was induced with a 10% guaifenesin solution administered intravenously via a pressurized pump followed by intubation and maintenance with 2% halothane. A ventral midline surgical approach exposed the uterus and the fetus was removed through a uterotomy. The placenta was manually stripped from the myometrial edges of the incision and the margins were oversewn using a continuous interlocking pattern. The uterus was then closed using a continuous Utrecht pattern and the uterus rotated 180 degrees back to its normal anatomical position. The abdomen was closed in 3 layers. Recovery of the llama was uneventful with the male cria able to nurse 6 hours post-operatively. Placental expulsion occurred approximately 48 hours after fetal removal.

Effect of latex and vinyl examination gloves on canine spermatozoal motility

Two experiments were conducted to determine whether contact with latex or vinyl examination gloves affects canine spermatozoal motility. In experiment 1, semen was collected by digital manipulation from each of 5 dogs, and initial spermatozoal motility was assessed. The ejaculate was divided into 5 equal subsamples of 2 ml each, then randomly assigned to a control group, or treated with a 0.5-cm2 piece of latex or vinyl glove with or without talcum powder. After such exposure, spermatozoal motility was assessed at 1 and 5 minutes. Talcum powder within latex or vinyl glove treatments had no significant effect on spermatozoal motility at either period. Spermatozoal motility in samples did not differ between the control and vinyl glove groups; however, latex glove-treated samples were found to have a significant (P less than 0.05) decrease in spermatozoal motility at 1 and 5 minutes. In experiment 2, the effects of latex and vinyl gloves on canine spermatozoal motility during a sham laboratory manipulation was performed. Three ejaculates of approximately 10 ml were collected from each of 5 dogs and randomly assigned, within each dog, to be either a control (no glove exposure) or allowed to briefly contact either a latex or vinyl glove during sample manipulation. Spermatozoal motility was assessed for each sample immediately prior to and at 1 minute after manipulation. Exposure of semen to latex gloves significantly (P less than 0.05) decreased sample spermatozoal motility, whereas vinyl glove exposure had a minimal (P greater than 0.05) effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Electroejaculation and artificial insemination in Vietnamese potbellied miniature pigs

A 15-month-old Vietnamese miniature boar was examined because of suspected infertility. A breeding soundness examination was conducted, using electroejaculation under anesthesia for semen collection. Semen values were normal despite a subpubic location of the testes. Artificial insemination of a gilt with extended semen resulted in the birth of a litter 111 days later. Vietnamese potbellied boars have small and sometimes nearly undetectable scrotal pouches, which may cause the producer to question the fertility of the boars.

Multiple congenital defects in a female calf: a case report

This case report describes a female calf with arthogryposis, an extra set of incision teeth, ventral abdominal hernia, tibial hemimelia and the nonunion of mullerian ducts. This is possibly the first occurrence of these anomalies in one animal. The cause of these anomalies may have been genetic in origin due to the close relationship between the dam and the sire and the negative history for such various tetragenic factors.

The effects of xylazine and alpha-adrenoreceptor antagonists on bovine uterine contractility in vitro

The effects of alpha-adrenoreceptor antagonists prazosin (alpha-1), yohimbine (alpha-2), and idazoxan (alpha-2) on xylazine-induced bovine uterine contractility were tested in vitro. Uterine strips from proestrous/estrous and diestrous cows were mounted in tissue baths containing Tyrode's solution. Changes in uterine contractility were measured by strain gauge. The following results were observed: 1) Xylazine increased uterine contractility in a dose dependent manner (cumulative concentrations: 10(-8), 3x10(-8), 10(-7), 3x10(-7) and 10(-6)M). 2) Idazoxan (10(-8), 10(-7) and 10(-6)M) and yohimbine (10(-6), 10(-5) and 10(-4)M) antagonized uterine contractility induced by xylazine in a dose-dependent manner. Idazoxan was approximately 50 to 100 times more potent than yohimbine. 3) Prazosin (10(-5)M) did not alter the effect of xylazine on uterine contractility. These results suggested that xylazine-induced uterine contractility in the cyclic cow is directly mediated by myometrial alpha-2 adrenoreceptors.

Effects of epidural administration of xylazine or lidocaine on bovine uterine motility and perineal analgesia

The objective of this study was to evaluate and compare the effects of caudal epidural (sacral-coccygeal interspace) administration of xylazine or lidocaine on uterine motility and perineal analgesia in the cow. Six Holstein cows (7 d post estrus) were assigned to one of three treatment groups: control (5 ml saline); lidocaine (0.2 mg/kg, 2% solution); and xylazine (0.06 mg/kg suspended in 5 ml saline), with each cow randomly assigned to each treatment over a period of three estrous cycles. Uterine motility, perineal analgesia, electrocardiography, and overt signs of sedation were recorded. Data were collected at 10-min intervals starting 10 min before treatment and continuing until 60 min post treatment. At 60 min post treatment, oxytocin (20 USP units) was administered i.v. to serve as a positive control for uterine motility. In the xylazine group, uterine motility significantly (P < 0.05) increased at 20 min post treatment, peaked at 30 min, and gradually decreased to non-significant levels at 50 min post treatment when compared with the lidocaine and control groups. Additionally, xylazine produced a higher degree and longer duration of perineal analgesia than lidocaine. Systemically, epidural xylazine produced signs of sedation, salivation, vocalization and bradycardia. Ataxia was also observed in the xylazine-treated group which may have been induced through a local and/or systemic effect. The individual properties of xylazine and lidocaine should be taken into consideration when performing an obstetrical procedure requiring the use of an epidural analgesic agent, and they should be utilized to benefit the clinician in performing the procedure.

Toxicity effects of latex gloves on boar spermatozoa

It is known that several materials used in semen collection have been found to be detrimental to spermatozoal motility. In this study, examinations for toxic effects of latex and vinyl gloves, used with and without talcum powder on boar spermatozoa, were performed. Ten boars of known fertility with >/=80% sperm motility were divided into two groups (n = 5 boars each) for in vitro and in vivo studies. In the in vitro study, semen was collected from each of the five boars and was divided into five separate aliquots (5 ml each). One aliquot from each of the boars remained as the control, while the remaining aliquots were divided into individual treatments exposing the semen to a l cm(2) piece of latex or vinyl glove with or without talcum powder. In the in vivo experiment, semen from each of the five boars was collected using a gloved hand. During collection, the first half of the sperm-rich fraction was collected into a filtered sterile container, while the second half of the fraction was allowed to run through the palm of either a latex or vinyl powdered glove prior to collection in the container. In both experiments, semen sample motility was assessed by two independent observers at 1 minute after exposure. Results of both experiments consistently showed a significant (P<0.05) effect of latex gloves (with or without talcum powder) on boar semen when compared with the control semen. Motility was at or near 0% at 1 min after exposure to latex. No significant difference (P>0.05) in motility was observed between the control semen and the semen exposed to talcum powdered vinyl gloves. These results show that latex gloves are detrimental to boar spermatozoa. Therefore, it is suggested that when collecting boar semen vinyl gloves should be used.

Farrowing induction with cloprostenol-xylazine combination

Eighty crossbred, multiparous sows, weighing between 190 and 320 kg, were randomly assigned to the following four treatment groups of 20 sows each: 1) saline-saline, 2) cloprostenol-saline, 3) saline-xylazine and 4) cloprostenol-xylazine. The mean gestation length of each multiparous sow was calculated. Cloprostenol (250 ug/sow, i.m.) or saline was given 3 d prior to the calculated due date at 11:30 a.m. Xylazine (2 mg/kg, i.m.) or saline was given 20 h after either the cloprostenol or previous saline treatment. Cloprostenol-xylazine treated sows had the shortest mean farrowing interval (1.5 +/- 0.3 h) when compared with the rest of the treatment groups (saline-saline:66.0 +/- 8.1, cloprostenol-saline:10.5 +/- 1.9, saline-xylazine:60.6 +/- 5.6 h). Farrowing time, percentage of stillbirths, average birth weight, d-5 and d-21 postbirth weights, number of pigs born, number of pigs born alive, and number of pigs surviving at 5 and 21 d afterbirth were not significantly different among the four groups. This study demonstrated that cloprostenol-xylazine treatment decreases the time to onset of farrowing with less variation than cloprostenol or xylazine alone. Therefore, the use of a cloprostenol-xylazine combination is suggested as an alternative method for inducing farrowing.

Prescribing patterns in agoraphobia with panic attacks

Although medication is used commonly in the treatment of agoraphobia with panic attacks, the actual drug-prescribing patterns of the medical profession have not been well studied in this condition. The present study compares the prescribing patterns of general practitioners and psychiatrists in their treatment of agoraphobia with panic attacks. The medical records of 111 agoraphobic patients with panic attacks were analysed and divided into those who were referred by general practitioners and those who were referred by psychiatrists. Over all, in the treatment of agoraphobia with panic attacks, general practitioners prescribed drugs less often than did psychiatrists. They used fewer combinations of drugs and tended to prescribe tricyclic antidepressant agents in doses which generally are considered to be below the therapeutic range. This finding would suggest that general practitioners are less effective than are psychiatrists in prescribing for this condition as judged by current practice, although they are less likely to prescribe combinations of drugs--a practice which might well be to their credit.

Effect of population structure on protein-yield improvements in spring wheat (Triticum aestivum L. em Thell)

In a study designed to develop a more efficient breeding method for concurrent protein-yield improvements in wheat (Triticum aestivum L. em. Thell), 7 base populations [2 F2's, 1 intermated F2 (IF2) and 4 partial backcross (PBC) populations] developed from biparental crosses involving 2 Canadian hard red spring (CHRS) and 2 Canadian utility (CU) wheat cultivars were evaluated in Winnipeg, Manitoba, Canada. The IF2 and PBC populations were generated for comparison with conventional F2 populations and to determine which of the 4 methods of population development would provide a more efficient means of producing potentially superior genetic recombinants. Parameters pertaining to means, variances, correlations, heritabilities and frequencies of desirable and undesirable progenies were used to evaluate the limitations to genetic gain that may be expected from selection for GY and GPC in F2, IF2, CHRS-PBC and CU-PBC populations. Analysis of protein and yield data from 105 S1 lines derived from each of the 7 populations showed the CU-PBC's to have the highest grain yield (GY) and the lowest grain protein concentration (GPC) means; and the CHRS-PBC's, the lowest GY and the highest GPC means. The F2 and IF2 populations were intermediate for both characteristics. Populations developed from the same biparental cross did not differ significantly with respect to the majority of genetic parameters. However, desirable progenies combining high GY with high GPC were more frequent in the CU-PBC, and least frequent in the CHRS-PBC populations. The observed superiority of the CU-PBC populations appeared to be related to the advantage the system has in preserving the genetic integrity of a proven cultivar, while adding desirable genetic factors from another cultivar, thus capitalizing on introgression and upgrading simultaneously.

Testicular changes observed in boars following experimental inoculation with pseudorabies (Aujeszky's) virus

Four boars were inoculated intranasally with pseudorabies virus to determine if microscopic testicular changes occurred as a result of infection. Testicular biopsies and semen samples were taken at two, four and six weeks postinoculation and the boars were castrated immediately after the last sample collection. Testicular samples and semen were cultured to determine if the virus was present. Pseudorabies virus was not isolated from the semen or testicular tissue. Virus was isolated from trigeminal ganglia at necropsy and from nasal swabs taken one day after castration. Consequently, a time of high risk for shed of the virus from clinically normal carrier animals is immediately following castration. Gross changes were not observed in testicular tissues and microscopic changes in the testicles were the result of biopsy. Lesions consistent with pseudorabies virus infection were observed in the central nervous system of all inoculated boars. Temporary lowered fertility may result from the effects of elevated body temperature on spermatogenesis during acute clinical disease. However, it appears that the strain of pseudorabies virus used, lacked the ability to infect and/or replicate in the boars' reproductive tracts.

The effect of pseudorabies (Aujeszky's) virus infection on young mature boars and boar fertility

This study was designed to determine the effects of experimental inoculation with pseudorabies virus on the reproductive tracts of young adult boars. Pseudorabies virus was inoculated intranasally into 12 boars and intrapreputially into four boars. All animals seroconverted after nasal or preputial inoculation. Semen abnormalities were observed 21 days postinoculation with partial recovery by 50 days postinoculation. Virus was isolated from the preputial sheath of two intrapreputially inoculated boars 12 days postinoculation. It was concluded that pseudorabies virus infection can be established via preputial inoculation and that decreased spermatogenesis and infertility can result.

Antigenic relationships among some bovine rotaviruses: serum neutralization and cross-protection in gnotobiotic calves

A method was further developed to screen non-tissue-culture-adapted bovine rotaviruses for serotype, using a neutralization test with infectious fecal rotavirus. One of those rotaviruses (B223) which was not blocked by antiserum to the neonatal calf diarrhea virus (NCDV) serotype was then adapted to cell culture in the presence of the antiserum for two or more passages and hyperimmune antiserum to this isolate had a 60-fold-higher homologous neutralization titer than with the NCDV serotype rotavirus. Seventy-three isolates were serotyped and eight (11%) were not of the NCDV serotype (bovine rotavirus serotype I). Of these eight, five belonged to the new bovine rotavirus serotype II and three were not typed, indicating the existence of one or more further serotypes. Cross-protection studies in gnotobiotic calves showed that cross-protection only occurred between rotaviruses of the same serotype, and even a minor serotype difference was sufficient for the calves to show a lack of cross-protection. The serotypes (I and II and the three untyped isolates) also showed differences in the rate of migration in polyacrylamide gel electrophoresis of some of their RNA segments (no. 4, 6, 7, 8, 9, 10), indicating that they were of different electropherotypes.

Comparison of sperm-rich fractions of boar semen collected by electroejaculation and the gloved-hand technique

Semen was collected from 8 yearling boars, using electroejaculation and the gloved-hand technique. Four semen samples were collected from each boar by each technique, on an alternating schedule, with a 72-hour interval between collections. Comparison of the volume, motility, live-dead ratio, sperm concentration, and spermatozoal conformation of the sperm-rich fractions showed that there were no significant differences between the 2 techniques for any factor evaluated.

Expanded polytetrafluoroethylene femoropopliteal grafts: forty-eight-month follow-up

Ninety-eight expanded polytetrafluoroethylene (PTFE) grafts were used for femoropopliteal reconstruction in 81 patients. Forty-eight-month follow-up is now available for 20 grafts and 36-month follow-up is available for 51 grafts. Seventy-four percent of the patients were men. Thirty-one percent had diabetes mellitus, 38% had hypertension, 36% had atherosclerotic heart disease, 18% had prior myocardial infarction, 17% had a previous operation for aortoiliac disease, and 14% had a previous ipsilateral femoropopliteal bypass procedure. The indication for operation was claudication in 47%, rest pain in 20%, and ischemic pregangrene or gangrene in 32% of patients. Distal runoff was angiographically graded as good (76%) or poor (24%). Seventy-three grafts were anastomosed to the proximal or midpopliteal artery (above the knee); 25 grafts were anastomosed to the distal popliteal artery (below the knee). Graft occlusion was determined by the return of ischemic symptoms, disappearance of previously palpable pulses, or by angiographic or Doppler assessment. There were no operative deaths. Nonocclusive causes of graft loss were death (7), amputation (2), infection (2), and aneurysm (5). The overall cumulative patency rate calculated by the life-table method, according to the criterion of occlusion alone, was 75% at 6 months, 68% at 2 years, 58% at 3 years, and 48% at 4 years. Preoperative symptoms, the number of patent outflow vessels, popliteal anastomosis placed above or below the knee, or hypertension did not adversely affect graft patency. Diabetes mellitus was associated with significantly increased graft failure. The PTFE graft is an acceptable alternative for femoropopliteal reconstruction for the patient without a suitable autologous saphenous vein.

Drugs and depression

Moderate or severe depression is now one of the most common diseases of our time with a prevalence of nearly 3%. It seems likely that this prevalence has increased as a result of the wider use of drugs which have an effect on the neurotransmitters. Changes in the levels of these neurotransmitters in the central nervous system are thought to be the biochemical basis for the development of at least some depressive illnesses. Drug-induced depressions are more likely to occur in those individuals who are genetically predisposed to depression or who have had a previous depressive illness. Other groups who are particularly susceptible to these effects are the elderly. Many groups of drugs have a primary or secondary action on the central nervous system neurotransmitter function. Some 200 drugs have been claimed to cause depression in certain patients, but only a relatively small number precipitate depressive symptoms with any frequency. Those most commonly implicated are the long-acting antipsychotics, barbiturates, ethanol, oral contraceptives and antihypertensive agents. It is important to remember that some drugs, such as reserpine, cause depression as a side-effect during their therapeutic use whereas others, such as fenfluramine, cause depression mainly when they are withdrawn too rapidly. In those patients presenting with depression, it is important to review the current drug therapy in order to assess the part played by these drugs in the development of the depression. Following this assessment, drug therapy should be adjusted appropriately. However, a distinction must be made between the symptoms of depression, those physiological changes which occur during treatment with a variety of drugs, and the patient's reaction to the disease for which they are being treated.

Bovine plasma oestrogens, progesterone and glucocorticoids during dexamethasone induced parturition

Plasma samples were collected from jugular, uterine and utero-ovarian veins during glucocorticoid induced parturition. Plasma oestrogens, corticosteroids and progesterone were determined by competitive protein binding methods. Corticosteroids and progesterone began to decline within 8 to 10 h following DXMS treatment. Corticoids were only temporarily suppressed, while progesterone fell to minimum levels and remained low through calving. At this stage of gestation (270 days) peripheral plasma progesterone was primarily of ovarian origin. Pre-treatment with HCG appeared to support progesterone production by the CL despite DXMS treatment in 2 of 6 cows. These 2 cows failed to calve within the expected 96 h after DXMS. Plasma oestrogens did not show significant increased until 24 h after DXMS treatment. Cows which responded to DXMS treatment (calved) had significantly higher oestrogen levels than those which did not respond. It was concluded that oestrogens probably play a permissive rather than an initiating role in parturition.

A double-blind trial of intravenous thyrotrophin-releasing hormone in the treatment of reactive depression

In a double-blind trial 600 mug. of thyrotrophin-releasing hormone (TRH) was compared with placebo given daily for four days to two groups of ten patients. There was no significant difference between the antidepressant effects of TRH and placebo.

A versatile accessory for stationing corrugated rebreather tubes during surgery

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Durum-type wheat with high bread-making quality

A durum-type wheat (2n = 4x = 28) with high bread-making quality was produced by crossing a durum-wheat variety with a common bread-wheat variety (2n = 6x = 42), backcrossing to the bread-wheat variety for three generations, and then selecting for 28-chromosome plants. The high quality is tentatively attributed to a translocation involving one of the D-genome chromosomes.

Intramedullary Pinning of Bilateral Fractures of the Shaft of the Ilium

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