Place of therapeutic cannabis in France and safety data: A literature review.

OBJECTIVES: To date, very few cannabis-based specialities are authorised on the French market despite a growing demand from patients and health professionals. The objective of this study is to review the tolerance profile and the French legislative status of the two main cannabinoids used for therapeutic purposes: tetrahydrocannabiol (THC) associated with psychoactive effects and non-psychoactive cannabidiol (CBD). METHODS: This review is based on relevant articles retrieved by a search in Google Scholar and PubMed databases and on an assessment of the legal texts and summaries of product characteristics available in France. RESULTS: Evidence for the tolerability of CBD during chronic use is reassuring, but a significant risk of drug interactions exists. THC use appears to be associated with a higher proportion of serious adverse effects, including neuropsychological and cardiovascular effects. Inhaled cannabis appears to be associated with greater toxicity than the oral route. These data are presented together with the pharmacokinetic and pharmacodynamic data of THC and CBD. CONCLUSION: The literature reports several frequent but rarely serious adverse effects of CBD during chronic use as well as a significant risk of drug interactions. THC use seems to be associated with a higher proportion of serious adverse effects compared to CBD, particularly at the neuropsychological and cardiovascular levels. Health professionals should be up to date on the particularities of therapeutic cannabis in terms of efficacy, safety and drug interactions.

[History of Ketamine: An ancient molecule that is still popular today]. / Histoire de la kétamine : une molécule ancienne qui a toujours la cote.

The history of ketamine begins in 1962, when Calvin Stevens of the pharmaceutical laboratory Parke-Davis synthesizes it from phencyclidine, a molecule with psychodysleptic, hallucinogenic and dissociative properties. Following the first administration of ketamine to humans in 1964 in Jackson prison (Michigan, USA), its dissociative effects associated with short anaesthesia were reported, and a patent for its human use was filed in 1966. In the 1990s, the discovery of opioid-induced hyperalgesia sparked interest in ketamine as an analgesic. In recent years, the human use of ketamine, and in particular its esketamine enantiomer, has shifted towards the treatment of depression. The first cases of ketamine abuse were reported in 1992 in France, leading to special surveillance by the health authorities, and its inclusion in the list of narcotic drugs in 1997. Today, ketamine has become an attractive substance for recreational use, gradually emerging from alternative techno circles to spread to more commercial party scenes. These elements represent a public health concern, associated with the risk of developing new chemically synthesized analogues, the harmful effects of which are still little known.

Cx30.2 deletion causes imbalances in testicular Cx43, Cx46, and Cx50 and insulin receptors. Reciprocally, diabetes/obesity alters Cx30.2 in mouse testis.

Cx30.2 protein content and localization were assessed during development. An account of Cx30.2, Cx43, Cx46, and Cx50, and insulin receptor (IR) responses to Cx30.2, Cx46, or Cx50 deficiency in mouse interstitial tissue (ITf)- and seminiferous tubule-enriched fractions (STf) is given. The impact of high glucose/insulin on Cx30.2 was investigated in spontaneously diabetic and obese db/db and ob/ob mouse testis and anterior pituitary (AP). Cx30.2 labeled contacts in vascular endothelial and Leydig cells and Sertoli cell junctions in stage V-VII. Cx30.2 expression is regulated differently in the interstitium and tubules. Cx30.2 at 30-kDa levels peaked by 28 days in ITf and by 14 days in STf. In STf, deleting Cx30.2 decreased Cx43 and Cx50, whereas deleting Cx50 downregulated Cx30.2. The opposite occurred in ITf. In STf, deleting Cx30.2 upregulated Cx46 except the full-length reciprocally, deleting Cx46 upregulated Cx30.2. In ITf, Cx30.2 deficiency upregulated full-length and phosphorylated Cx46, whereas deleting Cx46 downregulated 48- to 50-kDa Cx30.2. The db/db and ob/ob mouse ITf, STf, and AP showed imbalanced Cx30.2 levels. IRα levels at 135 kDa declined in Cx30.2-/- and Cx50-/- mouse ITf and Cx46-/- and Cx50-/- STf. IRß at 98 to 110 kDa dropped in Cx30.2-/- and Cx46-/- mice STf suggesting that Cx30.2 deficiency decreases active IR sites. The results show the connexins interdependence and interaction and that altering a single connexin changes the remaining connexins expression, which can modify gap junction-mediated glucose exchanges in contacting cells. Data suggest that glucose/insulin influences Cx30.2 turnover in testis and AP and, reciprocally, that connexins modulate testis glucose uptake and response to insulin.

Glucose, insulin, insulin receptor subunits α and ß in normal and spontaneously diabetic and obese ob/ob and db/db infertile mouse testis and hypophysis.

BACKGROUND: Type 2 diabetes touches young subjects of reproductive age in epidemic proportion. This study assesses glucose, total InsulinT, Insulin2 and insulin receptor subunits α and ß in testis during mouse development then, in the spontaneously type 2 diabetes models associated with infertility db/db and ob/ob mice. IR-ß and α were also assessed in spermatozoa (SPZ), anterior pituitary (AP) and serum. METHODS: Serum and tissue glucose were measured with enzymatic colorimetric assays and InsulinT and Insulin2 by ELISAs in serum, interstitial tissue- (ITf) and seminiferous tubule (STf) fractions in14- > 60-day-old normal and db/db, ob/ob and wild type (WT) mice. IR subunits were assessed by immunoblotting in tissues and by immunoprecipitation followed by immunoblotting in serum. RESULTS: Development: Glucose increased in serum, ITf and STf. InsulinT and Insulin2 dropped in serum; both were higher in STf than in ITf. In > 60-day-old mouse ITf, insulinT rose whereas Insulin2 decreased; InsulinT and Insulin2 rose concurrently in STf. Glucose and insulin were high in > 60-day-old ITf; in STf high insulin2 accompanied low glucose. One hundred ten kDa IR-ß peaked in 28-day-old ITf and 14-day-old STf. One hundred thirty five kDa IR-α was high in ITf but decreased in STf. Glucose escalated in db/db and ob/ob sera. Glucose doubled in ITf while being halved in STf in db/db mice. Glucose significantly dropped in db/db and ob/ob mice spermatozoa. InsulinT and Insulin2 rose significantly in the serum, ITf and STf in db/db and ob/ob mice. One hundred ten kDa IR-ß and 135 kDa IR-α decreased in db/db and ob/ob ITf. Only 110 kDa IR-ß dropped in db/db and ob/ob STf and AP. One hundred ten kDa IR-ß fell in db/db and ob/ob SPZ. One hundred ten kDa sIR-α rose in the db/db and ob/ob mouse sera. CONCLUSION: Insulin regulates glucose in tubules not in the interstitium. The mouse interstitium contains InsulinT and Insulin2 whereas tubules contain Insulin2. Decreased 110 kDa IR-ß and 135 kDa IR-α in the db/db and ob/ob interstitial tissue suggest a loss of active receptor sites that could alter the testicular cell insulin binding and response to the hormone. Decreased IR-ß levels were insufficient to stimulate downstream effectors in AP and tubules. IR-α shedding increased in db/db and ob/ob mice.

Cholesterol metabolism and Cx43, Cx46, and Cx50 gap junction protein expression and localization in normal and diabetic and obese ob/ob and db/db mouse testes.

Decreased fertility and birth rates arise from metabolic disorders. This study assesses cholesterol metabolism and Cx46, Cx50, and Cx43 expression in interstitium- and seminiferous tubule-enriched fractions of leptin-deficient ( ob/ob) and leptin receptor-deficient ( db/db) mice, two type 2 diabetes and obesity models associated with infertility. Testosterone levels decreased and glucose and free and esterified cholesterol (FC and EC) levels increased in serum, whereas FC and EC levels decreased in the interstitium, in ob/ob and db/db mice. In tubules, a decrease in EC caused FC-to-EC ratios to increase in db/db mice. In tubules, only acyl coenzyme A:cholesterol acyl transferase type 1 and 2 protein levels significantly decreased in ob/ob, but not db/db, mice compared with wild-type mice, and imbalances in the cholesterol transporters Niemann-Pick C1 (NPC1), ATP-binding cassette A1 (ABCA1), scavenger receptor class B member I (SR-BI), and cluster of differentiation 36 (CD36) were observed in ob/ob and db/db mice. In tubules, 14-kDa Cx46 prevailed during development, 48- to 49- and 68- to 71-kDa Cx46 prevailed during adulthood, and total Cx46 changed little. Compared with wild-type mice, 14-kDa Cx46 increased, whereas 48- to 49- and 68- to 71-kDa Cx46 decreased, in tubules, whereas the opposite occurred in the interstitium, in db/db and ob/ob mice. Total and 51-kDa Cx50 increased in db/db and ob/ob interstitium and tubules. Cx43 levels decreased in ob/ob interstitium and tubules, whereas Cx43 decreased in db/db interstitium but increased in db/db tubules. Apoptosis levels measured by ELISA and numbers of apostain-labeled apoptotic cells significantly increased in db/db, but not ob/ob, tubules. Testicular db/db capillaries were Cx50-positive but weakly Cx43-positive with a thickened lamina, suggesting altered permeability. Our findings indicate that the db mutation-induced impairment of meiosis may arise from imbalances in cholesterol metabolism and upregulated Cx43 expression and phosphorylation in tubules.

The Incremental Cost of Incompatible Living Donor Kidney Transplantation: A National Cohort Analysis.

Incompatible living donor kidney transplantation (ILDKT) has been established as an effective option for end-stage renal disease patients with willing but HLA-incompatible living donors, reducing mortality and improving quality of life. Depending on antibody titer, ILDKT can require highly resource-intensive procedures, including intravenous immunoglobulin, plasma exchange, and/or cell-depleting antibody treatment, as well as protocol biopsies and donor-specific antibody testing. This study sought to compare the cost and Medicare reimbursement, exclusive of organ acquisition payment, for ILDKT (n = 926) with varying antibody titers to matched compatible transplants (n = 2762) performed between 2002 and 2011. Data were assembled from a national cohort study of ILDKT and a unique data set linking hospital cost accounting data and Medicare claims. ILDKT was more expensive than matched compatible transplantation, ranging from 20% higher adjusted costs for positive on Luminex assay but negative flow cytometric crossmatch, 26% higher for positive flow cytometric crossmatch but negative cytotoxic crossmatch, and 39% higher for positive cytotoxic crossmatch (p < 0.0001 for all). ILDKT was associated with longer median length of stay (12.9 vs. 7.8 days), higher Medicare payments ($91 330 vs. $63 782 p < 0.0001), and greater outlier payments. In conclusion, ILDKT increases the cost of and payments for kidney transplantation.

Excess psychosocial burden in women with diabetes and premature acute coronary syndrome.

AIM: Diabetes is a stronger risk factor for acute coronary syndrome for women than men. We investigate whether behavioural and psychosocial factors contribute to the disparity in acute coronary syndrome risk and outcomes among women with diabetes relative to women without diabetes and men. METHODS: Among 939 participants in the GENESIS-PRAXY cohort study of premature acute coronary syndrome (age ≤ 55 years), we compared the prevalence of traditional and non-traditional factors by sex and Type 2 diabetes status. In a case-only analysis, we used generalized logit models to investigate the influence of traditional and non-traditional factors on the interaction of sex and diabetes. RESULTS: In 287 women (14.3% with diabetes) and 652 men (10.4% with diabetes), women and men with diabetes showed a heavier burden of traditional cardiac risk factors compared with individuals without diabetes. Women with diabetes were more likely to be the primary earner and have more anxiety relative to women without diabetes, and reported worse perceived health compared with women without diabetes and men with diabetes. The interaction term for sex and diabetes (odds ratio (OR) 1.40, 95% confidence intervals (95% CI) 0.83-2.36) was diminished after additional adjustment for non-traditional factors (OR 1.12, 95% CI 0.54-2.32), but not traditional factors alone (OR 1.41, 95% CI 0.84-2.36). CONCLUSIONS: We observed trends toward a more adverse psychosocial profile among women with diabetes and incident acute coronary syndrome compared with women without diabetes and men with diabetes, which may explain the increased risk of acute coronary syndrome in women with diabetes and may also contribute to worse outcomes.

The Incorporation of an Advanced Donation Program Into Kidney Paired Exchange: Initial Experience of the National Kidney Registry.

The continued growth of kidney paired donation (KPD) to facilitate transplantation for otherwise incompatible or suboptimal living kidney donors and recipients has depended on a balance between the logistics required for patients and the collaborating transplant centers. The formation of chains for KPD and the shipping of kidneys have permitted networks such as the National Kidney Registry (NKR) to offer KPD to patients over a transcontinental area. However, over the last 3 years, we have encountered patient requests for a more flexible experience in KPD to meet their individual needs often due to rigid time constraints. To accommodate these requests, we have developed an Advanced Donation Program (ADP) in which the donor desires to donate by a specific date, but their paired recipient has not yet been matched to a specific donor or scheduled for surgery. After obtaining careful informed consent from both the donor and paired recipient, 10 KPD chains were constructed using an ADP donor. These 10 ADP donors have facilitated 47 transplants, and thus far eight of their paired recipients have received a kidney within a mean of 178 (range 10-562) days. The ADP is a viable method to support time limited donors in a KPD network.

Complementary expression and phosphorylation of Cx46 and Cx50 during development and following gene deletion in mouse and in normal and orchitic mink testes.

Gap junction-mediated communication helps synchronize interconnected Sertoli cell activities. Besides, coordination of germ cell and Sertoli cell activities depends on gap junction-mediated Sertoli cell-germ cell communication. This report assesses mechanisms underlying the regulation of connexin 46 (Cx46) and Cx50 in mouse testis and those accompanying a "natural" seasonal and a pathological arrest of spermatogenesis, resulting from autoimmune orchitis (AIO) in mink. Furthermore, the impact of deleting Cx46 or Cx50 on the expression, phosphorylation of junction proteins, and spermatogenesis is evaluated. Cx46 mRNA and protein expression increased, whereas Cx50 decreased with adulthood in normal mice and mink. Cx46 mRNA and protein expression increased, whereas Cx50 decreased with adulthood in normal mice and mink. During the mink active spermatogenic phase, Cx50 became phosphorylated and localized to the site of the blood-testis barrier. By contrast, Cx46 was dephosphorylated and associated with annular junctions, suggesting phosphorylation/dephosphorylation of Cx46 and Cx50 involvement in the barrier dynamics. Cx46-positive annular junctions in contact with lipid droplets were found. Cx46 and Cx50 expression and localization were altered in mink with AIO. The deletion of Cx46 or Cx50 impacted on other connexin expression and phosphorylation and differently affected tight and adhering junction protein expression. The level of apoptosis, determined by ELISA, and a number of Apostain-labeled spermatocytes and spermatids/tubules were higher in mice lacking Cx46 (Cx46-/-) than wild-type and Cx50-/- mice, arguing for life-sustaining Cx46 gap junction-mediated exchanges in late-stage germ cells secluded from the blood by the barrier. The data show that expression and phosphorylation of Cx46 and Cx50 are complementary in seminiferous tubules.

Key role for CD4 T cells during mixed antibody-mediated rejection of renal allografts.

We utilized mouse models to elucidate the immunologic mechanisms of functional graft loss during mixed antibody-mediated rejection of renal allografts (mixed AMR), in which humoral and cellular responses to the graft occur concomitantly. Although the majority of T cells in the graft at the time of rejection were CD8 T cells with only a minor population of CD4 T cells, depletion of CD4 but not CD8 cells prevented acute graft loss during mixed AMR. CD4 depletion eliminated antidonor alloantibodies and conferred protection from destruction of renal allografts. ELISPOT revealed that CD4 T effectors responded to donor alloantigens by both the direct and indirect pathways of allorecognition. In transfer studies, CD4 T effectors primed to donor alloantigens were highly effective at promoting acute graft dysfunction, and exhibited the attributes of effector T cells. Laser capture microdissection and confirmatory immunostaining studies revealed that CD4 T cells infiltrating the graft produced effector molecules with graft destructive potential. Bioluminescent imaging confirmed that CD4 T effectors traffic to the graft site in immune replete hosts. These data document that host CD4 T cells can promote acute dysfunction of renal allografts by directly mediating graft injury in addition to facilitating antidonor alloantibody responses.

Quantifying the risk of incompatible kidney transplantation: a multicenter study.

Incompatible live donor kidney transplantation (ILDKT) offers a survival advantage over dialysis to patients with anti-HLA donor-specific antibody (DSA). Program-specific reports (PSRs) fail to account for ILDKT, placing this practice at regulatory risk. We collected DSA data, categorized as positive Luminex, negative flow crossmatch (PLNF) (n = 185), positive flow, negative cytotoxic crossmatch (PFNC) (n = 536) or positive cytotoxic crossmatch (PCC) (n = 304), from 22 centers. We tested associations between DSA, graft loss and mortality after adjusting for PSR model factors, using 9669 compatible patients as a comparison. PLNF patients had similar graft loss; however, PFNC (adjusted hazard ratio [aHR] = 1.64, 95% confidence interval [CI]: 1.15-2.23, p = 0.007) and PCC (aHR = 5.01, 95% CI: 3.71-6.77, p < 0.001) were associated with increased graft loss in the first year. PLNF patients had similar mortality; however, PFNC (aHR = 2.04; 95% CI: 1.28-3.26; p = 0.003) and PCC (aHR = 4.59; 95% CI: 2.98-7.07; p < 0.001) were associated with increased mortality. We simulated Centers for Medicare & Medicaid Services flagging to examine ILDKT's effect on the risk of being flagged. Compared to equal-quality centers performing no ILDKT, centers performing 5%, 10% or 20% PFNC had a 1.19-, 1.33- and 1.73-fold higher odds of being flagged. Centers performing 5%, 10% or 20% PCC had a 2.22-, 4.09- and 10.72-fold higher odds. Failure to account for ILDKT's increased risk places centers providing this life-saving treatment in jeopardy of regulatory intervention.

Dysregulation of testicular cholesterol metabolism following spontaneous mutation of the niemann-pick c1 gene in mice.

The Niemann-Pick-type C1 (Npc1) protein mobilizes LDL-derived cholesterol from lysosomes. Npc1 deficiency disease is a panethnic autosomal recessive disorder of intracellular cholesterol trafficking, leading to accumulation of cholesterol in endosomes/lysosomes. This report assesses the effects of a spontaneous inactivating mutation of the Npc1 gene on spermatogenesis and cholesterol homeostasis in mice. We quantified 1) free and esterified cholesterol levels by enzymatic analysis, 2) cholesterol enzymes and transporter protein expression by Western blotting, and 3) the number of Apostain-labeled apoptotic germ cells and apoptosis levels by ELISA in seminiferous tubule-enriched fractions. In wild-type (WT) mice, esterified cholesterol was elevated when Npc1 expression was low during puberty, while in adulthood, the levels were low (P < 0.05) when Npc1 expression was high (P < 0.01). In Npc1-/- mice, free and esterified cholesterol were significantly elevated. The abundance of cholesterol regulatory proteins, HMGR ACAT1, ACAT2, SR-BI, and ABCA1 was significantly higher in Npc1-/- than in WT mice. The level of apoptosis determined by ELISA and the number of Apostain-labeled cells/tubule were higher in Npc1-/- than in WT mice. Circulating testosterone levels in the Npc1-/- males were threefold lower than those observed in the WT. Deleting the Npc1 gene is accompanied by an increase in germ cell apoptosis and compensatory imbalances in the expression of cholesterol enzymatic and transporter factors and is associated with esterified cholesterol accumulation in seminiferous tubules.

Endemic human blastomycosis in Quebec, Canada, 1988-2011.

Blastomycosis is a systemic fungal infection found in various parts of the world. A review of literature for Quebec, Canada revealed only few case reports with the most recent one dating back to 1993. However, whether Quebec represents an important endemic region for blastomycosis in North America is unknown. In this work we reviewed 158 cases of human blastomycosis documented in Quebec during 1988-2011 using microbiological records available from the provincial public health laboratory. The estimated annual incidence of blastomycosis in the province is was ~0·133 cases per 100 000 individuals with the highest rates of 0·79 and 0·46 cases per 100 000 recorded in South-eastern and South-western Quebec. Moreover, the annual incidence rate significantly increased over the past 20 years. This study for the first time establishes Quebec as an important endemic region for Blastomyces dermatitidis.

The pathogenesis of acute allograft dysfunction in desensitized renal transplant recipients.

BACKGROUND: Acute allograft rejection after HLA desensitization is common early post-transplant but the sequence of histopathologic changes leading to graft dysfunction has not been well defined. METHODS: We evaluated the early pathogenesis and sequence of antibody-mediated graft damage of 35 desensitized living donor kidney recipients by studying the course of biopsies taken in the very early post-transplant period (<1 month). RESULTS: A total of 14 of the 35 patients met criteria for acute antibody-mediated rejection (AMR). In these patients, the chronologic sequence of pathologic changes was C4d peritubular capillary deposition, acute tubular injury, and peritubular capillaritis, followed by glomerulitis and interstitial inflammation. Classic AMR lesions occurred early, followed by mononuclear cellular infiltration, which comprised CD4 and CD8 T cells and monocytes. Development of graft dysfunction in most patients occurred concurrently with the emergence of graft cellular infiltration, rather than at the earlier time of antibody deposition as detected via C4d deposition. CONCLUSION: These data provide novel insight into the sequence of pathologic changes in patients with AMR post-transplant after HLA desensitization.

PCSK9 Contributes to the Cholesterol, Glucose, and Insulin2 Homeostasis in Seminiferous Tubules and Maintenance of Immunotolerance in Testis.

The PCSK9 contribution to cholesterol and immunotolerance homeostasis and response to glucose, and insulin in testis and hypophysis were studied using Pcsk9-deficient (-/-) and transgenic [Tg (PCSK9)] mice, and diabetic, obese ob/ob and db/db mice. The spermatids/spermatozoa acrosome, peritubular vessels, and epididymal adipocytes were PCSK9- and LDL-R-positive. The pro-PCSK9/PCSK9 ratio was high in interstitial tissue-fractions (ITf) and spermatozoa and low in seminiferous tubule-fractions (STf) in normal adult mice. This ratio decreased in ITf in ob/ob and db/db mice but increased in tubules in ob/ob mice. Deleting pcsk9 lowered cholesterol in serum but increased testicular cholesterol. Furthermore, HMGCoA-red, ACAT-2 and LDL-R turnover increased whereas SR-BI decreased in ITf; in tubules, ABCA1 decreased and 160 kDa LDL-R increased in Pcsk9 -/- mice. Excess testicular cholesterol could result from increased cholesterol synthesis and uptake with reduction in SR-BI-mediated efflux in ITf and from the overload of apoptotic cells, lowered ABCA1-mediated efflux and stimulated LDL-R protein synthesis in tubules in Pcsk9 -/- mice. Concomitantly with the cholesterol accumulation, tubules showed infiltrates of immune cells, elevated IL-17A and IL-17RA, and changes in the immunotolerance homeostasis. PCSK9 deficiency decreased glucose in tubules and spermatozoa while increasing insulin2 in ITf and tubules not serum. Moreover, IR-α, and IR-ß augmented in tubules but decreased in the anterior pituitary; IR-α increased whereas IR-ß decreased in ITf. The histology and cholesterol levels were normal in Tg (PCSK9) mouse testis. The excess cholesterol creates a milieu favorable to the action of high IL-17A and IL-17RA, the development of inflammatory conditions and self-tolerance breakdown in testis.

CX43 expression, phosphorylation, and distribution in the normal and autoimmune orchitic testis with a look at gap junctions joining germ cell to germ cell.

Spermatogenesis requires connexin 43 (Cx43).This study examines normal gene transcription, translation, and phosphorylation of Cx43 to define its role on germ cell growth and Sertoli cell's differentiation, and identifies abnormalities arising from spontaneous autoimmune orchitis (AIO) in mink, a seasonal breeder and a natural model for autoimmunity. Northern blot analysis detected 2.8- and a 3.7-kb Cx43 mRNA bands in seminiferous tubule-enriched fractions. Cx43 mRNA increased in seminiferous tubule-enriched fractions throughout development and then seasonally with the completion of spermatogenesis. Cx43 protein levels increased transiently during the colonization of the tubules by the early-stage spermatocytes. Cx43 phosphorylated (PCx43) and nonphosphorylated (NPCx43) in Ser368 decreased during the periods of completion of meiosis and Sertoli cell differentiation, while Cx43 mRNA remained elevated throughout. PCx43 labeled chiefly the plasma membrane except by stage VII when vesicles were also labeled in Sertoli cells. Vesicles and lysosomes in Sertoli cells and the Golgi apparatus in the round spermatids were NPCx43 positive. A decrease in Cx43 gene expression was matched by a Cx43 protein increase in the early, not the late, phase of AIO. Total Cx43 and PCx43 decreased with the advance of orchitis. The study makes a novel finding of gap junctions connecting germ cells. The data indicate that Cx43 protein expression and phosphorylation in Ser368 are stage-specific events that may locally influence the acquisition of meiotic competence and the Sertoli cell differentiation in normal testis. AIO modifies Cx43 levels, suggesting changes in Cx43-mediated intercommunication and spermatogenic activity in response to cytokines imbalances in Sertoli cells.

Characterization of chicken Sertoli cells in vitro.

In the testis, Sertoli cells play a key physiological role in that they support, nourish, and protect germ cells. Because of the importance of Sertoli cells, several laboratories have established a culture system of Sertoli cells. These cultures have been well developed in mammalian species, but to our knowledge no purified avian Sertoli cells culture has been described. The aim of this study was to isolate avian Sertoli cells and to investigate their function using a chicken model in an in vitro test system. Immature chicken Sertoli cells in culture present morphology similar to that of mammalian cells and conserve expression of the specific Sertoli marker, anti-Müllerian hormone. Furthermore, in contrast to mammals, they express the 3ß-hydroxysteroid dehydrogenase enzyme. Stimulation of Sertoli cells with ovine follicle-stimulating hormone rapidly activates the 3 main downstream signaling pathways of the follicle-stimulating hormone receptor: cyclic( )adenosine monophosphate/protein kinase A, phosphatidylinositol 3-kinase/Akt, and mitogen-activated protein kinase pathways. In vitro, Sertoli cells are able to secrete lactate and inhibin and have conserved the phagocytosis property. Finally, avian Sertoli cells present 3 interesting characteristics: they actively proliferate in vitro, can be passaged several times, and are suitable for freezing in nitrogen. A direct consequence of these properties is to use this cell culture test system as an alternative method to bird reprotoxicity studies.

Scavenger receptor-B1 and luteal function in mice.

During luteinization, circulating high-density lipoproteins supply cholesterol to ovarian cells via the scavenger receptor-B1 (SCARB1). In the mouse, SCARB1 is expressed in cytoplasm and periphery of theca, granulosa, and cumulus cells of developing follicles and increases dramatically during formation of corpora lutea. Blockade of ovulation in mice with meloxicam, a prostaglandin synthase-2 inhibitor, resulted in follicles with oocytes entrapped in unexpanded cumulus complexes and with granulosa cells with luteinized morphology and expressing SCARB1 characteristic of luteinization. Mice bearing null mutation of the Scarb1 gene (SCARB1(-/-)) had ovaries with small corpora lutea, large follicles with hypertrophied theca cells, and follicular cysts with blood-filled cavities. Plasma progesterone concentrations were decreased 50% in mice with Scarb1 gene disruption. When SCARB1(-/-) mice were treated with a combination of mevinolin [an inhibitor of 3-hydroxy-3-methylglutaryl CoA reductase (HMGR)] and chloroquine (an inhibitor of lysosomal processing of low-density lipoproteins), serum progesterone was further reduced. HMGR protein expression increased in SCARB1(-/-) mice, independent of treatment. It was concluded that theca, granulosa, and cumulus cells express SCARB1 during follicle development, but maximum expression depends on luteinization. Knockout of SCARB1(-/-) leads to ovarian pathology and suboptimal luteal steroidogenesis. Therefore, SCARB1 expression is essential for maintaining normal ovarian cholesterol homeostasis and luteal steroid synthesis.

De novo thrombotic microangiopathy in renal allograft biopsies-role of antibody-mediated rejection.

The most common cause of thrombotic microangiopathy (TMA) in renal allografts is thought to be calcineurin inhibitor toxicity. Antibody-mediated rejection (AMR) can also cause TMA, but its true impact on de novo TMA is unknown. In a retrospective review of renal allograft biopsies from January 2003 to December 2008 at our institution, we determined the prevalence of TMA in patients with C4d positive (n = 243) and C4d negative (n = 715) biopsies. Over 90% of patients received cyclosporine in both groups. De novo TMA was seen in 59 (6.1%) patients; most of them (55%) with C4d positive biopsy. Among patients with C4d positive biopsies, 13.6% had TMA, as compared to only 3.6% patients with C4d negative biopsies (p < 0.0001). Incidence of graft loss between C4d positive and C4d negative TMA groups was not significantly different, but 70% of patients with C4d positive TMA who received plasmapheresis had slightly lower graft loss rate. In biopsies with AMR-associated TMA, glomerulitis and peritubular capillaritis were significantly more prominent. AMR is the most common cause of TMA in renal allografts in our patient population. It is important to recognize AMR-related TMA because plasmapheresis treatment may be beneficial.