Fetal propofol and dexmedetomidine exposure during elective c-section in the bitch: impact on pup viability

Elective C-section is a common procedure recommended in dogs at risk of dystocia(1). Anesthetics administered at surgery can cross the placenta leading to distress up to neonatal mortality(2). The study aims to determine the impact on pup viability of a new anesthetic-analgesic protocol for elective C-section in the bitch. For this purpose, propofol (PPF) and dexmedetomidine (DEX) concentrations in maternal blood, amniotic fluid and placental tissue were correlate to neonatal parameters. Nine purebred bitches (age 4,9±2,3 years; weight 39,8±10,4 kg) were induced with a combination of PPF at 2,5 mg/kg and DEX at 2 μg/kg IV and maintained with isoflurane in 100% oxygen for elective C-section. If needed, additional doses of PPF were administered to effect in order to achieve intubation of patients. DEX and PPF quantification from the different biological matrices was carried out by HPLC-MS and HPLC-FL methods. Neonatal viability at birth was assessed with a modified Apgar score(3) (AS) and birth weight recorded as well as mortality of pups within 48 hours of life. Results: A total of 54 pups was delivered, 77,80% of them recorded as vigorous by AS. Neonatal mortality was 11,1%. Lowest AS was assigned to pups from mothers receiving additional dose of PPF. AS was not influenced by birth weight of pups, nor by maternal and placental drugs concentrations. Maternal blood PPF (range 0,24-2,8- mcg/mL) and DEX (range 0,41-2,04 ng/mL), and placental PPF (range 0,24-2,57 mcg/mL) concentrations tended to decrease over time, while placental DEX (range 1,32-6,15 ng/mL) was fairly uniformly detected in pups from the same litter. DEX concentration in placenta was much higher than in maternal blood showing a greater placental retention compared with PPF. Both PPF and DEX were not detectable in amniotic fluid. Placenta resulted an effective barrier against fetal DEX exposure making this protocol safe, analgesic and advisable for elective C-section in dog. (1) Moon PF, Erb HN, Ludders JW, et al. Perioperative Risk Factors for Puppies Delivered by Cesarean Section in the United States and Canada. J Am Anim Hosp Assoc 2000;36:359-68. (2) Luna SPL, Cassu RN, Castro GB et al. Effects of four anaesthetic protocols on the neurological and cardiorespiratory variables of puppies born by caesarean section. Vet Rec 2004;154:387–89 (3) Groppetti D, Pecile A, Del Carro AP, et al. Evaluation of newborn canine viability by means of umbilical vein lactate measurement, apgar score and uterine tocodynamometry. Theriogenology 2010;74(7):1187-96

Immunohistochemical insights into a hidden pathology : Canine cryptorchidism

Cryptorchidism is a common disorder in the canine population with some aspects still unclear. Although the bilateral condition is known to lead to fertility problems and predisposition to testicular cancer, the neoplastic risk for scrotal testis in unilateral cryptorchid dog is controversial. Therefore, the therapeutic approach to the canine unilateral cryptorchid is arbitrary so far. This study aimed to investigate precancerous testicular lesions, such as immaturity and atrophy, and compare them in scrotal and undescended testes using an in-depth diagnostic analysis based on immunophenotypic patterns. With this purpose, 26 adult male dogs of different ages and breeds, affected by unilateral or bilateral cryptorchidism were enrolled. After surgical removal, testes were examined immunohistochemically to assess their positivity for specific markers of the canine foetal/neonatal period, that is vimentin (VIM), cytokeratin (CK), desmin (DES), inhibin-α (INH), and anti-Müllerian hormone (AMH) in Sertoli cells, and placental alkaline phosphatase (PLAP) in germ cells. Except for the ubiquitous VIM, all the markers were more expressed in neoplastic gonads compared to healthy ones (P < 0.05). Similarly, testes detected with Sertoli cell-only tubules as well as with Sertoli cells hyperplasia showed higher expression than gonads without such alterations for CK, DES, AMH and PLAP, and for CK and DES, respectively (P < 0.05). The same trend was observed in undescended respect to scrotal testes even though their positivity was significant only for DES, INH and AMH (P < 0.05). Immunohistochemical positivity found in scrotal testes of unilateral cryptorchid dogs, even in absence of detectable anatomical abnormalities, was suggestive of precancerous lesions. Despite the limited sample size, this study could help to clarify the predisposition to neoplastic development in normally descended testes. These markers expression in adult life could allow identifying the early stages of the testicular carcinogenesis process besides suggesting a precautionary bilateral surgical approach in unilateral cryptorchid dogs

Can peri-surgical electroacupuncture relieve immunity suppression? A pilot study in dogs

General anesthesia and surgical stress can suppress the immunological response by acting both directly on the immune system and indirectly on the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Disturbance of the immune system during the perioperative period can lead to complications such as wound-healing disorders and infections up to sepsis. Effectiveness of acupuncture in regulating the immune function by increasing leukocyte numbers and inhibiting inflammatory response has been proven. This study aimed to explore the impact of electroacupuncture (EAP) on the dynamic balance of the immune system and immune cell populations in dogs undergoing surgery. Twelve healthy bitches scheduled for elective ovariectomy were divided into two groups according to whether (EAP, n=6) or not (CTR, n=6) a peri-operative electroacupuncture treatment was performed. Levels of leukocytes (neutrophils, monocytes, T- and B-cells) and immunoglobulins M (IgM) and A (IgA) were measured in blood samples collected before (T0), 1 hour (T1) and 2.5 hours (T2) after anesthesia induction. Leukocytes count decreased from T0 to T1 in both groups and restored within 1.5 hours in EAP group whereas remained significantly lower in CTR group (P<0.02). In particular, neutrophils and monocytes increased in dogs receiving EAP (P<0.01) while T-cells decreased in CTR group (P<0.04) at T2. B-cells and cytotoxic T-cells decreased in EAP dogs (P<0.04) at T2. No differences in helper T-cells, IgM and IgA levels were recorded between groups and over time. Our results suggest a modulatory effect of EAP on the immune system which is early expressed on neutrophils, monocytes and T-cells

Neonatal mortality in dogs : prognostic value of Doppler ductus venosus waveform evaluation - Preliminary results

Aim: To define the prognostic value of Doppler ultrasonographic morphology of ductus venosus (DV) waveform on canine neonatal mortality. Materials and Methods: Fifty-four healthy pregnant bitches underwent fetal ultrasonographic assessment. The DV waveforms were classified as diphasic (dDVw) or triphasic (tDVw) and compared with neonatal mortality. Results: Ninety-three fetuses were evaluated. Twenty fetuses belonged to litters with neonatal mortality, in which tDVw was observed. Seven fetuses belonged to litters without neonatal mortality, in which tDVw was observed. Fifty-eight fetuses belonged to litters without neonatal mortality, in which only dDVw was observed. Eight fetuses belonged to litters with neonatal mortality, in which only dDVw was observed. The correlation between tDVw and neonatal mortality was statistically significant (odds ratio [OR], 20.7; p<0.0001). Considering only pregnancies with one or two fetuses with the same DV waveform: Two fetuses with tDVw belonged to litters with neonatal mortality; 1 foetus with tDVw belonged to litter without neonatal mortality and 26 fetuses showed dDVw without neonatal mortality. The correlation between tDVw and neonatal mortality even in litters up to two pups was statistically significant (OR, 88.3; p=0.01). Conclusion: Echo-Doppler assessment of DV is feasible in canine fetuses, and the presence tDVw seems to be related to neonatal mortality

Asymptomatic unilateral ovarian leiomioma in a German shepherd bitch

This report shows for the first time clinical imaging (ultrasound and computed tomography), histological and immunohistochemical findings of an ovarian leiomyoma, coincidentally diagnosed in an asymptomatic unmated nulliparous ten year-old German shepherd bitch concurrently suffering from multiple mammary tumors. A thorough examination allowed the differentiation of ovarian leiomyoma from other spindle cell tumors. An accurate description of the diagnostic procedures useful in the managing of ovarian leiomyoma could provide valuable information to veterinary practitioners. Indeed, despite its rarity and nonspecific symptoms, ovarian leiomyoma may also affect the dog with an unknown potential risk

The methylome of the hypothalamus of prepubertal and pubertal goats

Puberty is the fulfillment of fertility, a process involving physiological and morphological development. It is well known that the increased hypothalamic secretion of the gonadotropin-releasing hormone (GnRH) is essential for the activation of this process, even if the elements coordinating the timing of puberty have not been fully identified1,2. Recent studies provide proof that there is an epigenetic regulation of female puberty, and DNA methylation, the most studied epigenetic modification, plays a major role in it3. We analyzed DNA methylation patterns of 5 Alpine goats at their prepubertal stage and 5 that reached puberty in order to highlight differences in their methylome. Detection of methylated regions across the goat genome involved a Methyl Binding Domain (MBD) enrichment followed by deep sequencing (Hiseq2000 Illumina). The software ChIPseeqer4 permitted the identification of peaks corresponding to hyper-methylated regions. We have observed a higher methylation level in prepubertal goats. The distribution of the methylation peaks across the genome and within CpG islands per chromosome per group of animals has been analyzed. Furthermore, we have investigated differential methylation in genes associated with puberty. Specifically, Cbx7, coding for a core component of the Polycomb group silencing complex, and GnRHR, the gene coding for GnRH receptor, showed a higher number of peaks into two intragenic fragments within prepubertal goats. These results, accompanied by transcriptome analysis, provide a foundation for elucidating the role of DNA methylation in the complex mechanisms that drive puberty in goat species

Novel effect of nefopam preventing cGMP increase, oxygen radical formation and neuronal death induced by veratridine

Nefopam hydrochloride is a potent analgesic compound that possesses a profile distinct from that of opiods or anti-inflammatory drugs. Previous evidence suggested a central action of nefopam but the detailed mechanisms remain unclear. Here we have used cultured cerebellar neurons to test the hypothesis that nefopam may modulate voltage sensitive sodium channel (VSSC) activity. Nefopam (100 microM) effectively prevented NMDA receptor-mediated early appearance (30 min) of toxicity signs induced by the VSSC activator veratridine. Delayed neurotoxicity by veratridine occurring independently from NMDA receptor activation, was also prevented by nefopam. In contrast, excitotoxicity following direct exposure of neurons to glutamate was not affected. Neuroprotection by nefopam was dose-dependent. 50% protection was obtained at 57 microM while full neuroprotection was achieved at 75 microM nefopam. Veratridine-induced sodium influx was completely abolished in nefopam-treated neurons. Intracellular cGMP and oxygen radical formation following VSSC stimulation by veratridine were also effectively prevented by nefopam. Our data are consistent with an inhibitory action of nefopam on VSSC and suggest that nefopam may modulate the release of endogenous glutamate following activation of these channels. This novel action of nefopam may be of great interest for the treatment of neurodegenerative disorders involving excessive glutamate release and neurotransmission

A first glance on the epigenome of Capra hircus

DNA methylation and microRNAs (miRNA) are two important forms of epigenetic modifications that play an important role in gene regulation in animals. Methylation at the carbon 5 position of cytosine residues is a fundamental layer of cellular differentiation through the control of transcriptional potential. MiRNA are small noncoding RNA molecules that regulate gene expression. Complete DNA methylomes for several organisms are now available; at the present, methylome of the domestic goat is unexplored. There is also still limited knowledge about miRNAs expression profiles in small ruminant species. Therefore, to contribute information on epigenetic modification in Capra hircus, we analysed the methylome and the miRNA population of three tissues (hypothalamus, pituitary and ovary) from 3 adult Saanen goats. We used Methylated DNA binding domain sequencing with enrichment of methylated DNA fragments and next generation sequencing. We produced least 23 million reads per sample, which were aligned to the goat reference genome. Further analyses were performed to identify peaks corresponding to hyper-methylated regions. We sequenced miRNAs expressed in the three tissues with Illumina high-throughput sequencing. Reads were mapped on the Capra hircus reference genome and both known and novel miRNAs, and miRNA target sites were identified using information collected in miRBase and using specific bioinformatic tools. This study produced a comprehensive miRNA profile related to the biology of goat. Furthermore, this is the first work dealing with methylome in Capra hircus: our preliminary results could provide new information for a deeper comprehension of epigenetic mechanisms of this species

Nefopam, an analogue of orphenadrine, protects against both NMDA receptor-dependent and independent veratridine-induced neurotoxicity

Nefopam hyghochloride is a potent analgesic compound commercialized in most Western Europe for 20 years, which possesses a profile distinct from that of opioids or anti-inflammatory drugs. Previous evidence suggested a central action of nefopam but the detailed mechanisms remain unclear. While, nefopam structure resembles that of orphenadrine, an uncompetitive NMDA receptor antagonist, here we report that differently from orphenadrine, nefopam (100 microM) failed to protect cultured cerebellar neurons from excitotoxicity following direct exposure of neurons to glutamate. Moreover, nefopam failed to displace MK-801 binding to hippocampal membranes. Nefopam effectively prevented NMDA receptor-mediated early appearance (30 min) of toxicity signs induced by the voltage sensitive sodium channel (VSSC) activator veratridine. The later phase (24 h) of neurotoxicity by veratridine occurring independently from NMDA receptor activation, was also prevented by nefopam. Nefopam effect was not mimicked by the GABA receptor agonist muscimo