Enteric viruses replicate in salivary glands and infect through saliva.

Enteric viruses like norovirus, rotavirus and astrovirus have long been accepted as spreading in the population through fecal-oral transmission: viruses are shed into feces from one host and enter the oral cavity of another, bypassing salivary glands (SGs) and reaching the intestines to replicate, be shed in feces and repeat the transmission cycle1. Yet there are viruses (for example, rabies) that infect the SGs2,3, making the oral cavity one site of replication and saliva one conduit of transmission. Here we report that enteric viruses productively and persistently infect SGs, reaching titres comparable to those in the intestines. We demonstrate that enteric viruses get released into the saliva, identifying a second route of viral transmission. This is particularly significant for infected infants, whose saliva directly transmits enteric viruses to their mothers' mammary glands through backflow during suckling. This sidesteps the conventional gut-mammary axis route4 and leads to a rapid surge in maternal milk secretory IgA antibodies5,6. Lastly, we show that SG-derived spheroids7 and cell lines8 can replicate and propagate enteric viruses, generating a scalable and manageable system of production. Collectively, our research uncovers a new transmission route for enteric viruses with implications for therapeutics, diagnostics and importantly sanitation measures to prevent spread through saliva.

Higher serum levels of a cathepsin K-generated periostin fragment are associated with fractures in postmenopausal women with primary hyperparathyroidism: a pilot study.

The only difference between fractured and non-fractured postmenopausal women with PHPT of same sex, age, and BMI was a significantly mean higher serum k-periostin level. K-periostin value was associated with fracture at any site (odds ratio 1.044, 95% CI 1.005-1.091, p = 0.03). INTRODUCTION: To assess serum k-periostin fragment levels in patients with primary hyperparathyroidism (PHPT), fractured and non-fractured matched for sex, age, and body mass index. METHODS: Twenty-five Caucasian fractured postmenopausal women with PHPT (group Fx) and 25 PHPT non-fractured (group NFx) were enrolled. Each patient underwent DXA scan at lumbar, hip, and forearm, spine X-ray, and biochemical evaluation of calcium metabolism. For k-periostin analyses, we utilized a specific ELISA test that detects CatK-generated fragment levels in the bloodstream. RESULTS: We found no difference in mean BMD and bone turnover marker values between Fx and NFx groups. Prevalence of osteoporosis was not significantly different in Fx vs NFx (72% vs 60%, p = 0.55). Among Fx, 16% reported multiple fractures, 28% morphometric vertebral fractures, 4% femoral fractures, 28% non-vertebral non-femoral fractures, and 8% wrist fractures. The only detectable difference between Fx and NFx group was a significantly mean higher k-periostin serum level (46.2 ± 21.4 vs 34.7 ± 13.5 ng/ml, p = 0.02). K-periostin was associated with fracture at any site (odds ratio 1.044, 95% CI 1.005-1.091, p = 0.03). No difference in mean k-periostin values was found between patients with vertebral fracture vs those with non-vertebral fracture, and between those with multiple fractures vs those with single fracture. CONCLUSION: Serum k-periostin is significantly associated with fracture in PHPT. If confirmed by further studies, k-periostin could be considered a new marker of bone fragility in PHPT, independently of BMD.

Lymphomatoid papulosis types D and E: a multicentre series of the French Cutaneous Lymphomas Study Group.

BACKGROUND: Lymphomatoid papulosis (LyP) type D (LyP D) and type E (LyP E) have recently been described in small series of cases or isolated case reports. AIM: To further describe the clinical and histological features of LyP D and E based on a retrospective multicentre study. METHODS: The clinical and histopathological features of 29 patients with an initial diagnosis of LyP D or LyP E were retrospectively assessed using standardized forms. RESULTS: After exclusion of 5 cases, 24 patients (14 LyP D, 10 LyP E) were enrolled in the study. The median follow-up was 2.5 years (range 1 month to 13 years). LyP D was characterized by multiple recurrent self-regressing small papules that developed central erosion or necrosis, whereas LyP E presented as papulonodular lesions that rapidly evolved into necrotic eschar-like lesions > 10 mm in size. Epidermal changes were more frequent in LyP D, whereas dermal infiltrates were deeper in LyP E. Anaplastic cytology was rare and the DUSP22 rearrangement was never observed. Two patients (8%) had an associated cutaneous lymphoma. CONCLUSION: LyP D and E have distinct clinical findings and may be associated with other cutaneous lymphomas.

Interaction between LRP5 and periostin gene polymorphisms on serum periostin levels and cortical bone microstructure.

We investigated the interaction between periostin SNPs and the SNPs of the genes assumed to modulate serum periostin levels and bone microstructure in a cohort of postmenopausal women. We identified an interaction between LRP5 SNP rs648438 and periostin SNP rs9547970 on serum periostin levels and on radial cortical porosity. PURPOSE: The purpose of this study is to investigate the interaction between periostin gene polymorphisms (SNPs) and other genes potentially responsible for modulating serum periostin levels and bone microstructure in a cohort of postmenopausal women. METHODS: In 648 postmenopausal women from the Geneva Retirees Cohort, we analyzed 6 periostin SNPs and another 149 SNPs in 14 genes, namely BMP2, CTNNB1, ESR1, ESR2, LRP5, LRP6, PTH, SPTBN1, SOST, TGFb1, TNFRSF11A, TNFSF11, TNFRSF11B and WNT16. Volumetric BMD and bone microstructure were measured by high-resolution peripheral quantitative computed tomography at the distal radius and tibia. RESULTS: Serum periostin levels were associated with radial cortical porosity, including after adjustment for age, BMI, and years since menopause (p = 0.036). Sixteen SNPs in the ESR1, LRP5, TNFRSF11A, SOST, SPTBN1, TNFRSF11B and TNFSF11 genes were associated with serum periostin levels (p range 0.03-0.001) whereas 26 SNPs in 9 genes were associated with cortical porosity at the radius and/or at the tibia. WNT 16 was the gene with the highest number of SNPs associated with both trabecular and cortical microstructure. The periostin SNP rs9547970 was also associated with cortical porosity (p = 0.04). In particular, SNPs in LRP5, ESR1 and near the TNFRSF11A gene were associated with both cortical porosity and serum periostin levels. Eventually, we identified an interaction between LRP5 SNP rs648438 and periostin SNP rs9547970 on serum periostin levels (interaction p = 0.01) and on radial cortical porosity (interaction p = 0.005). CONCLUSION: These results suggest that periostin expression is genetically modulated, particularly by polymorphisms in the Wnt pathway, and is thereby implicated in the genetic variation of bone microstructure.

T-cell papulosis associated with B-cell malignancy: a distinctive clinicopathologic entity.

BACKGROUND: A distinctive eruption referred to as 'insect bite-like reaction' or 'eosinophilic dermatosis of haematological malignancy' has been described during the course of haematological B-cell malignancies (BCM). However, its clinical evolution, histopathological features and pathogenesis remain unclear. OBJECTIVES: To characterize this eruption and to investigate its pathogenesis and relationship with the underlying BCM. METHODS: In this multicenter retrospective study of the French Study Group on Cutaneous Lymphomas, 37 patients with a BCM and a cutaneous eruption consisting in chronic and/or recurrent papules, papulo-vesicles and/or nodules were included. Clinical, histopathological, immunohistochemical and molecular data were reviewed. RESULTS: No significant insect bite history or seasonal predominance was recorded. Patients had pruritic papules (81%), papulo-vesicles (43%) and nodules (38%), often predominated in the head and neck region (84%), without complete remission periods in most cases (57%). The predominant associated BCM was chronic lymphocytic leukaemia (73%). Histological and immunohistochemical review showed a dense dermal lymphocytic infiltrate predominantly composed of T lymphocytes (100%), with frequent eosinophils (77.6%); a perivascular and periadnexal (most often folliculotropic) pattern (77.6%), sometimes suggestive of a folliculotropic mycosis fungoides; clusters of tumour B cells were identified in 47% of cases using appropriate phenotyping markers. In 10/14 cases (71.4%) tested for B-cell IgH gene rearrangement, a B-cell clone was identified in skin lesions (identical to the blood clone in nine cases), whereas no T-cell clone was present. CONCLUSION: We propose the denomination 'T-cell papulosis associated with B-cell malignancy' (TCP-BCM) for this distinctive eruption. Although resulting in various histopathological pictures, it can be easily recognized by clinicians and may be identified by informed pathologists relying on some key features. An extravasation of tumour B cells with skin-homing properties associated with a secondary, predominant, T-cell immune reaction could explain the clinicopathologic aspect and the prolonged regressive and recurrent course of the disease.

Aortic arch registry of type a aortic dissection (AoArch) - rationale, design and definition criteria.

BACKGROUND: Type A acute aortic dissection (TAAAD) is a deadly condition that demands immediate surgery, because it involves a critically. The mortality and morbidity associated with it are significant, and it is vital that the patient's conditions and treatment strategies are fully understood to ensure the appropriate management of TAAAD. This study aims to ascertain whether hemiarch repair (HAR) versus extended arch repair (EAR) with or without descending aortic intervention results in better perioperative and late outcomes for patients with TAAAD. METHODS: Four leading centers of cardiac surgery from two European countries have joined forces to create a groundbreaking multicenter observational registry (AoArch). This study was approved by the institutional review board (IRB 202201173). We conducted a retrospective review (NCT00591263) of our prospectively maintained database for patients who underwent operative repair of DeBakey type I or type II dissection from January 1, 2005 to March 2024 (NCT05927090). We will analyze how patient co-morbidities, referral conditions, and surgical strategies involving hemi-arch repair (HAR) and extended arch repair (EAR) impact early and late adverse events. We have developed a procedure urgency algorithm based on the severity of preoperative hemodynamic conditions and malperfusion due to TAAAD, and we will use it to assess the primary clinical outcomes: in-hospital mortality, late mortality, and reoperations on the aorta. We will define secondary outcomes as permanent neurologic deficit, the need for new dialysis, respiratory failure, a composite of major adverse events (myocardial infarction, cerebrovascular accidents, the need for dialysis, or the need for tracheostomy), and a composite of major adverse pulmonary events (intubation over 48 h, pneumonia, reintubation, tracheostomy), and reoperation due to bleeding. DISCUSSION: This multicenter registry will definitively determine the prognostic significance of critical preoperative conditions and the efficacy of extended arch interventions and hemiarch repair in reducing the risk of early adverse events after surgery for TAAAD. This registry will provide insights into the long-term durability of different strategies of surgical repair for TAAAD.

[Papular mycosis fungoides]. / Mycosis fongoïde papuleux.

BACKGROUND: Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma. A new form of incipient MF has recently been described: papular MF. Herein, we report a case and propose a literature review. PATIENTS AND METHODS: A 63-year-old man presented with erythematous and non-pruritic papular lesions of the trunk. The general examination was unremarkable. A skin biopsy showed moderately dense epidermotropic lymphocytic infiltration consistent with MF. Screening for CD30 was negative. Treatment with an extremely potent corticosteroid (clobetasol, one application per day) seemed effective, with almost complete disappearance of the lesions. DISCUSSION: Many clinical variants of the initial stages of MF have been described, one of the most recent of which is papular mycosis fungoides (PMF), of which 10 cases are reported in the literature. PMF begins clinically with an erythematous, non-pruritic and chronic papular rash that is not associated with the classic erythematous-squamous lesions of incipient MF. There appears to be no predominance of gender, and the age of onset ranges from 31 to 63 years. Histological examination of the PMF lesions revealed an epidermotropic subepidermal infiltrate composed predominantly of CD4+T-cells. The prognosis appeared good with the treatments conventionally used for incipient MF. PMF is likened to a form of incipient MF with a good prognosis. Associated classic MF lesions comprising erythematous-squamous plaques have been described as the condition progresses. Differential diagnoses include pilotropic MF, pityriasis lichenoides chronica, pityriasis lichenoides varioliformis acuta, and especially type B lymphomatoid papulosis, the histopathological findings of which may be close to PMF. CONCLUSION: Papular MF would appear to be a papular variant of incipient MF with a good prognosis. However, it is necessary to obtain clinical and disease progression data for a greater number of patients in order to better characterize this entity.

Meiotic studies of a 38,XY/39,XXY mosaic boar.

Klinefelter's syndrome (KS) is the most common sex chromosome abnormality identified in human males. This syndrome is generally associated with infertility. Men with KS may have a 47,XXY or a 46,XY/47,XXY karyotype. Studies carried out in humans and mice suggest that only XY cells are able to enter and complete meiosis. These cells could originate from the XY cells present in mosaic patients or from XXY cells that have lost one X chromosome. In pig, only 3 cases of pure 39,XXY have been reported until now, and no meiotic analysis was carried out. For the first time in pig species we report the analysis of a 38,XY/39,XXY boar and describe the origin of the supplementary X chromosome and the chromosomal constitutions of the germ and Sertoli cells.

Two-year follow-up of 196 interstitial lung disease patients after ICU stay.

OBJECTIVE: Interstitial lung diseases (ILDs) are associated with poor prognosis in the intensive care unit (ICU). We aimed to assess factors associated with hospital mortality in ILD patients admitted to the ICU and to investigate long-term outcome.MATERIAL AND METHODS: This was a retrospective study in a teaching hospital specialised in ILD management. Patients with ILD who were hospitalised in the ICU between 2000 and 2014 were included. Independent predictors of hospital mortality were identified using logistic regression.RESULTS: A total of 196 ILD patients were admitted to the ICU during the study period. Overall hospital mortality was 55%. Two years after ICU admission, 70 (36%) patients were still alive. Of the 196 patients, 108 (55%) required invasive mechanical ventilation, of whom 21 (20%) were discharged alive from hospital. Acute exacerbation of ILD and multi-organ failure were highly associated with hospital mortality (OR 5.4, 95% CI 1.9-15.5 and OR 12.6, 95% CI 4.9-32.5, respectively).CONCLUSION: Hospital mortality among ILD patients hospitalised in the ICU was high, but even where invasive mechanical ventilation was required, a substantial number of patients were discharged alive from hospital. Multi-organ failure could lead to major ethical concerns.

[Cutaneous events during anti-TNF alpha therapy: a prospective observational study of 41 cases]. / Evénements cutanéomuqueux au cours des traitements par anti-TNF alpha : étude observationnelle prospective de 41 cas.

BACKGROUND: The cutaneous adverse effects of TNFalpha inhibitors and their potential implication in the onset of associated dermatoses remain poorly understood. PURPOSE: To describe the different clinical dermatological situations seen in patients treated with TNFalpha inhibitors. PATIENTS AND METHODS: We conducted a prospective, observational study of patients followed at the Dermatology Department of the CHU Nord university teaching hospital of Marseilles. All patients, referred by various departments, were treated with TNFalpha inhibitors and presented cutaneous events. RESULTS: Forty-one patients were included in the study. Various cutaneous manifestations were observed, including: 15 psoriatic rashes, six skin infections, three eczema rashes, three cases of lupic syndrome, two anaphylactic reactions to infusion and two cutaneous drug reactions. An original case of parapsoriasis was observed. Cutaneous tumors are rarely described. DISCUSSION: This study confirms the multiple clinical dermatological situations observed in patients treated with TNFalpha inhibitors and illustrates the need for good coordination between dermatologists and other specialists in order to ensure optimal management of this population.

Pregnancy and lactation, a challenge for the skeleton.

In this review we discuss skeletal adaptations to the demanding situation of pregnancy and lactation. Calcium demands are increased during pregnancy and lactation, and this is effectuated by a complex series of hormonal changes. The changes in bone structure at the tissue and whole bone level observed during pregnancy and lactation appear to largely recover over time. The magnitude of the changes observed during lactation may relate to the volume and duration of breastfeeding and return to regular menses. Studies examining long-term consequences of pregnancy and lactation suggest that there are small, site-specific benefits to bone density and that bone geometry may also be affected. Pregnancy- and lactation-induced osteoporosis (PLO) is a rare disease for which the pathophysiological mechanism is as yet incompletely known; here, we discuss and speculate on the possible roles of genetics, oxytocin, sympathetic tone and bone marrow fat. Finally, we discuss fracture healing during pregnancy and lactation and the effects of estrogen on this process.

Male meiotic segregation analyses of peri- and paracentric inversions in the pig species.

Inversions are well-known structural chromosomal rearrangements in humans and pigs. Such rearrangements generally have no effect on the carriers' phenotype. However, the presence of an inversion can lead to spermatogenesis impairments and to the production of unbalanced (recombinant) gametes, responsible for early miscarriages, stillbirth, or congenital abnormalities. Sperm samples from boars heterozygote for pericentric inv(2)(p1.1;q1.1), inv(2) (p1.1;q2.1), inv(1)(p2.1;q2.10), or inv(1)(p2.4;q2.9), as well as for paracentric inv(2)(q1.3;q2.5) or inv(1)(q1.2;q2.4) were analyzed using sperm FISH (fluorescent in situ hybridization on decondensed sperm heads) to determine the male meiotic segregation profiles of the rearrangements. Furthermore, the availability of sperm samples for 2 unrelated carriers of inv(2)(p1.1;q1.1) allowed us to check for the occurrence of inter-individual variability of the rates of unbalanced meiotic products for this rearrangement. The estimated proportions of recombinant gametes were very low for all the inversions studied (0.62%, 1.30%, 3.05%, 1.27%, 4.12% and 0.84%, respectively), albeit significantly higher than the control. The rearrangements should therefore have very little impact on the reproductive performance of the carriers. No difference was found between the 2 carriers of inv(2)(p1.1;q1.1), suggesting a lack of inter-individual variability for this rearrangement. Overall, no significant correlation was found between the sizes of the inverted fragments and the proportions of recombinant (unbalanced) gametes for the 6 inversions studied. This is in contradiction with most human results. Further studies (pairing and recombination analysis using immunostaining techniques) should be carried out to elucidate the origin of such an inter-species difference.

Influence of sex on the meiotic segregation of a t(13;17) Robertsonian translocation: a case study in the pig.

BACKGROUND: Comparison of male versus female meiotic segregation patterns for Robertsonian translocation (RT) carriers with similar genetic background has rarely been reported in mammalian species. METHODS: The aim of this study was to compare the segregation patterns determined for related males and females carrying a 13;17 RT in an animal model (Sus scrofa domestica L.), using dual colour fluorescence in situ hybridization on decondensed sperm nuclei and metaphases II of in vitro-matured oocytes. RESULTS: In males, no association between the trivalent and the XY body was observed in any of the 90 pachytene nuclei studied, and the rate of unbalanced spermatozoa ranged between 2.96% and 3.83%. Female meiotic segregation analyses were carried out on 83 metaphase II oocytes. The rate of unbalanced gametes was higher in females than in males (28.91% versus 3.21%, P < 0.001). This difference was due to higher rates of diploid gametes (12.04% versus 0.05%) and unbalanced gametes produced by the adjacent segregation (16.86% versus 3.16%). CONCLUSIONS: This study is a new scientific contribution to the comparison of segregation patterns in related males and females carrying an identical chromosomal rearrangement. It allows a better understanding of the meiotic behaviour of RTs. It also clearly illustrates the relevance of swine as an animal model for such meiotic studies.

Assessment of trabecular bone microarchitecture by two different x-ray microcomputed tomographs: a comparative study of the rat distal tibia using Skyscan and Scanco devices.

Important aspects of modern skeletal research depend on the phenotypical characterization of trabecular bone microarchitecture as assessed by microcomputed tomography (micro-CT). Until now, however, there have been no studies which compare the two most commonly utilized micro-CT devices, namely, Skyscan and Scanco. The purpose of the current study was to examine the reproducibility and accuracy of these two micro-CT devices in comparison to traditional histomorphometry in ovariectomized rats treated with either propranolol, salbutamol, or vehicle. 6 month old female Wistar rats were ovariectomized (n = 48) or sham operated (n = 12). OVX rats were divided into four groups and then subcutaneously injected with propranolol 0.1 mg/kg/day, propranolol 20 mg/kg/day, salbutamol 3 mg/kg/day, or vehicle for 10 weeks. At sacrifice, the left tibial trabecular bone microarchitecture was analyzed using both the micro-CT Skyscan 1072 (ex vivo) and Scanco vivaCT40 (in vivo). Histomorphometric analysis was performed on the right proximal tibia. Comparisons between the different methods were performed using regression analysis, Bland-Altman, Passing-Bablock, and Mountain plots. Correlations were highly significant for all parameters measured between the two micro-CT instruments and were less significant between histomorphometry and micro-CT measurements taken from either the Skyscan or Scanco apparatus. Micro-CT overestimated bone volume compared to histomorphometry. In the ovariectomized rat model, the two micro-CT instruments revealed the same difference between groups whereas histomorphometry revealed only the difference which displayed the largest disparity between groups. In regards to the comparison between the two micro-CT devices, Mountain plot methods indicated that BV/TV, BS/BV, and TbSp were equivalent, whereas a systematic bias was observed for TbN and TbTh. The authors were also able to describe the routine method used to determine the threshold between the two micro-CT devices, which may help explain these differences. While some minor differences in the absolute values of the morphometry parameters exist between the micro-CT measurements from the Skyscan and Scanco instruments, both of these devices display a high degree of accuracy and reproducibility.

[Rhabdomyolysis in patients treated by corticosteroids for acute asthma in intensive care unit]. / La corticothérapie, une cause de rhabdomyolyse chez les asthmatiques en réanimation.

INTRODUCTION: Acute muscle involvement is an infrequent complication of corticosteroids, characterized by muscle weakness and a rhabdomyolysis, rapidly regressive after withdrawal of corticosteroids. CASE REPORT: We report the case of a woman admitted in intensive care unit for acute severe asthma, treated with high doses of methylprednisolone. Serum CPK level raised with a peak at 28,160 UI/L (n<250 UI/L) at day 15, suggesting acute rhabdomyolysis with renal failure. CPK rapidly normalized when corticosteroids were discontinued. Other causes of rhabdomyolysis were ruled out. CONCLUSION: This necrosing myopathy under high doses of corticosteroids has been described in patients with severe acute asthma. The mechanism of the muscle damage results from a combination of corticosteroids toxicity, respiratory acidosis and mechanic ventilation.

Millepora platyphylla (Cnidaria, Hydrozoa) range extended back to the Eastern Pacific, thanks to a new record from Clipperton Atoll.

The fire coral Millepora platyphylla Hemprich Ehrenberg, 1834 (Cnidaria, Hydrozoa) has a widespread Indo-Pacific distribution observed from the surface to 40 m (Razak Hoeksema 2003). However, its extirpation from the East Pacific (Gulf of Chiriqui, Panama) was documented after the 1982-1983 bleaching event (Glynn Weerdt 1991). Here, we report the discovery of 5 colonies of M. platyphylla from the eastern Pacific, specifically at Clipperton Atoll, during the TARA Pacific expedition (www.taraexpeditions.org).

Low dose beta-blocker prevents ovariectomy-induced bone loss in rats without affecting heart functions.

Findings from animal studies have suggested that bone remodeling is under beta-adrenergic control. However, the level of adrenergic inhibition required to achieve the most favorable effects on the skeleton remains unknown. To address this question, we compared the effects of low (0.1 mg/Kg/day), medium (5 mg/Kg/day) or high (20 mg/Kg/day) doses of propranolol given 5 days per week for 10 weeks in ovariectomized (OVX) rats. Characteristics of bone microarchitecture, biomechanical properties and bone turnover were investigated, whilst heart functions were assessed by echocardiography and catheterization of the left ventricle. We first confirmed the expression of Adrbeta2R and the absence of Adrbeta1R on osteoblasts by PCR and confocal microscopy. We then showed that low dose propranolol prevented OVX induced bone loss by increasing bone formation (+30% of MAR vs. placebo, P = 0.01) and decreasing bone resorption (-52% of osteoclast surface on bone surface vs. placebo, P = 0.01). Consequently, rats receiving 0.1 mg/kg/day propranolol displayed higher stress (+27%), intrinsic energy (+28.7%) and Young's Modulus in compression versus placebo (all, P < 0.05). No significant effects on heart hemodynamic parameters were found in rats receiving this dose. In contrast, medium and high doses of propranolol had a negative effect on heart functions but no significant protective effects on bone mass in ovariectomized rats. These results, consistent with the dominant nature of the high bone mass phenotype and normal heart function of Adrbeta2R-deficient mice, suggest that low doses of beta-blockers may have a therapeutic utility in the treatment of osteoporosis with high selectivity for bone tissues.

Meiotic studies in an azoospermic boar carrying a Y;14 translocation.

A reciprocal translocation between the q arm of the Y chromosome and the q arm of chromosome 14 was identified in a young, phenotypically normal boar presenting azoospermia. Testicular biopsies were analyzed by classical histological and immunolocalization techniques, and by fluorescence in situ hybridization. Meiotic pairing analysis of 85 pachytene spreads showed the presence of an open structure corresponding to a quadrivalent formed by chromosomes 14, X, and the derivative chromosomes 14 and Y in 84.7% of the cases. In the remaining cases (15.3%), a 'trivalent plus univalent' configuration was observed. Immunolocalization of gammaH2AX revealed the presence of this modified histone in the chromatin domains of unsynapsed segments (centromeric region of chromosome 14) and spreading of the gammaH2AX signal from the XY body throughout chromosome 14 in 7.05% of the cells analyzed. The potential causes of the observed infertility, i.e. activation of meiotic checkpoints and/or silencing of genes necessary for the progression of meiosis, are discussed.