Grandmaternal smoke exposure reduces female fertility in a murine model, with great-grandmaternal smoke exposure unlikely to have an effect.

STUDY QUESTION: What effect does multigenerational (F2) and transgenerational (F3) cigarette smoke exposure have on female fertility in mice? SUMMARY ANSWER: Cigarette smoking has a multigenerational effect on female fertility. WHAT IS KNOWN ALREADY: It has been well established that cigarette smoking decreases female fertility. Furthermore, a growing body of evidence suggests that smoking during pregnancy decreases the fertility of daughters and increases cancer and asthma incidence in grandchildren and great-grandchildren. STUDY DESIGN, SIZE, DURATION: Six-week-old C57BL/6 female mice were exposed nasally to cigarette smoke or room air (controls) for 5 weeks prior to being housed with males. Females continued to be exposed to smoke throughout pregnancy and lactation until pups were weaned. A subset of F1 female pups born to these smoke and non-smoke exposed females were bred to create the F2 grandmaternal exposed generation (multigenerational). Finally, a subset of F2 females were bred to create the F3 great-grandmaternal exposed generation (transgenerational). The reproductive health of F2 and F3 females was examined at 8 weeks and 9 months. PARTICIPANTS/MATERIALS, SETTING, METHODS: Ovarian and oocyte quality was examined in smoke exposed and control animals. A small-scale fertility trial was performed before ovarian changes were examined using ovarian histology and immunofluorescence and/or immunoblotting analysis of markers of apoptosis (TUNEL) and proliferation (proliferating cell nuclear antigen (PCNA) and anti-Mullerian hormone (AMH)). Oocyte quality was examined using immunocytochemistry to analyze the metaphase II spindle and ploidy status. Parthenogenetic activation of oocytes was used to investigate meiosis II timing and preimplantation embryo development. Finally, diestrus hormone serum levels (FSH and LH) were quantified. MAIN RESULTS AND THE ROLE OF CHANCE: F2 smoke exposed females had no detectable change in ovarian follicle quality at 8 weeks, although by 9 months ovarian somatic cell proliferation was reduced (P = 0.0197) compared with non-smoke exposed control. Further investigation revealed changes between control and smoke exposed F2 oocyte quality, including altered meiosis II timing at 8 weeks (P = 0.0337) and decreased spindle pole to pole length at 9 months (P = 0.0109). However, no change in preimplantation embryo development was observed following parthenogenetic activation. The most noticeable effect of cigarette smoke exposure was related to the subfertility of F2 females; F2 smoke exposed females displayed significantly increased time to conception (P = 0.0042) and significantly increased lag time between pregnancies (P = 0.0274) compared with non-smoke exposed F2 females. Conversely, F3 smoke exposed females displayed negligible oocyte and follicle changes up to 9 months of age, and normal preimplantation embryo development. LARGE SCALE DATA: None. LIMITATIONS, REASONS FOR CAUTION: This study focused solely on a mouse model of cigarette smoke exposure to simulate human exposure. WIDER IMPLICATIONS OF THE FINDINGS: Our results demonstrate that grandmaternal cigarette smoke exposure reduces female fertility in mice, highlighting the clinical need to promote cessation of cigarette smoking in pregnant women. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the Australian Research Council, National Health and Medical Research Council, Hunter Medical Research Institute, Newcastle Permanent Building Society Charitable Trust, and the University of Newcastle Priory Research Centers in Chemical Biology, Healthy Lungs and Grow Up Well. The authors declare no conflict of interest.

Non-coding RNA in Spermatogenesis and Epididymal Maturation.

Testicular germ and somatic cells express many classes of small ncRNAs, including Dicer-independent PIWI-interacting RNAs, Dicer-dependent miRNAs, and endogenous small interfering RNA. Several studies have identified ncRNAs that are highly, exclusively, or preferentially expressed in the testis and epididymis in specific germ and somatic cell types. Temporal and spatial expression of proteins is a key requirement of successful spermatogenesis and large-scale gene transcription occurs in two key stages, just prior to transcriptional quiescence in meiosis and then during spermiogenesis just prior to nuclear silencing in elongating spermatids. More than 60 % of these transcripts are then stockpiled for subsequent translation. In this capacity ncRNAs may act to interpret and transduce cellular signals to either maintain the undifferentiated stem cell population and/or drive cell differentiation during spermatogenesis and epididymal maturation. The assignation of specific roles to the majority of ncRNA species implicated as having a role in spermatogenesis and epididymal function will underpin fundamental understanding of normal and disease states in humans such as infertility and the development of germ cell tumours.

Regulation of Nuclear Import During Differentiation; The IMP alpha Gene Family and Spermatogenesis.

Access to nuclear genes in eukaryotes is provided by members of the importin (IMP) superfamily of proteins, which are of alpha- or beta-types, the best understood nuclear import pathway being mediated by a heterodimer of an IMP alpha and IMP beta1. IMP alpha recognises specific targeting signals on cargo proteins, while IMP beta1 mediates passage into, and release within, the nucleus by interacting with other components of the transport machinery, including the monomeric guanine nucleotide binding protein Ran. In this manner, hundreds of different proteins can be targeted specifically into the nucleus in a tightly regulated fashion. The IMP alpha gene family has expanded during evolution, with only a single IMP alpha (Srp1p) gene in budding yeast, and three (IMP alpha1, 2/pendulin and 3) and five (IMP alpha1, -2, -3, -4 and -6) IMP alpha genes in Drosophila melanogaster and mouse respectively, which fall into three phylogenetically distinct groups. The fact that IMP alpha3 and IMP alpha2 are only present in metazoans implies that they emerged during the evolution of multicellular animals to perform specialised roles in particular cells and tissues. This review describes what is known of the IMP alpha gene family in mouse and in D. melanogaster, including a comparitive examination of their mRNA expression profiles in a highly differentiated tissue, the testis. The clear implication of their highly regulated synthesis during the course of spermatogenesis is that the different IMP alphas have distinct expression patterns during cellular differentiation, implying tissue/cell type-specific roles.

Dissociation of serum prolactin response to sequential thyrotropin-releasing hormone and chlorpromazine stimulation in patients with primary empty sella syndrome.

The presence of galactorrhea and/or hyperprolactinemia in patients with the primary empty sella syndrome (PESS) has been proposed to be of hypothalamic etiology. To further elucidate this possible mechanism, sequential testing of 19 subjects with PESS with 500 micrograms thyrotropin-releasing hormone (TRH), followed by the injection of 0.7 mg/kg chlorpromazine (CPZ) 150 minutes later, was compared with results obtained in 6 patients with idiopathic galactorrhea (IG) and 3 normal adult women in the early follicular phase of the menstrual cycle. The thyroid-stimulating hormone and prolactin (PRL) response to TRH was similar in all three groups. The mean maximal increase of serum PRL following CPZ, however, was 16.1 +/- 18.5 ng/ml (standard deviation) in the PESS group, whereas the mean maximal PRL response was 68.6 +/- 40.9 ng/ml in subjects with IG and 67.7 +/- 48.1 ng/ml in the seven normal women. The impaired responsiveness of CPZ in the PESS group was significant (P less than 0.05) when compared with the normal CPZ response in the other two groups. The results of this study suggest that patients with PESS may have hypothalamic dysfunction, and that sequential testing of subjects with TRH and CPZ may be of value in differentiating patients with PESS from those with IG.

Effect of cataract surgery and intraocular lenses on diabetic retinopathy.

We reviewed a series of 137 cataract extractions with intraocular lenses (IOLs) in patients with diabetes, mellitus between 1977 and 1983. All patients were followed for an average of 36 months to determine if they subsequently showed progression of diabetic retinopathy. Divided into groups according to the type of procedure and IOL received, they were compared for age, sex, duration of diabetes, treatment required for the diabetes, intraoperative complications, and follow-up period. Patients who had intracapsular cataract extractions with anterior chamber IOLs were three times as likely to show proliferative retinopathy as those who had extracapsular cataract extractions with posterior chamber IOLs. Insulin-dependent patients were three to four times more likely to show progression to proliferation than noninsulin dependent patients. We conclude that, while some procedures are riskier for the diabetic eye, extracapsular lens extraction with implantation of a posterior chamber lens does not imply an increased risk of development of proliferative retinopathy.

Traumatic facial arteriovenous malformations.

Traumatic arteriovenous malformations (AVM) represent an abnormal communication between arteries and veins and are usually complex. They occur most commonly in the extremities and are noted most often in military casualties. In the literature there are approximately 25 cases of traumatic AVM of the facial region which are angiographically documented. To these are added five documented cases from this paper, one which was proven at surgery, and one which was suspected from classical signs and symptoms but not diagnosed. The trauma leading to the AVM may be: penetrating, blunt, postsurgical, or inflammatory. A swelling of the face, pulsatile tinnitus, throbbing headache and bleeding comprise the main presenting symptoms. A bruit and thrill are usually present. Doppler ultrasonography and selective arteriography will provide the essential diagnostic information. Embolization therapy may be a helpful preoperative adjunct or may be the total therapy if surgery cannot be performed. Proper identification of the feeder vessels, surgical control of these vessels, total excision of the AVM with functional and cosmetic reconstruction of the tissue defect remain the basic principles of therapy.

Incidence of eye injuries in facial fractures: an analysis of 727 cases.

From 1973 to 1980, 727 patients with facial fractures received formal ophthalmologic consultation. The series included 174 mandible fractures, 29 nasal fractures, 436 midfacial fractures, and 88 frontal fractures. Of these, a total of 67% sustained some degree of ocular injuries. Seventy-nine percent of the eye injuries were categorized as temporary, 18% were serious, and 3% were blinding. Of the mandibular fractures, 29% had ocular injuries, 59% nasal fractures, 59% midfacial fractures, and 89% frontal fractures.

Late recurrence of a frontal sinus cholesteatoma.

The longest recorded recurrence of a frontal sinus cholesteatoma with involvement of the orbit, frontal bone, and floor of the anterior cranial fossa is presented. Radical surgery is required and often craniotomy is necessary. Bony reconstruction of defects should not be undertaken until recurrence has not been present for at least a year. A review of the literature and a discussion of the origin of cholesteatomas is given.

Nasolacrimal evaluation and surgery.

The lacrimal drainage system is a very important functional and anatomic assembly in the orbit and midface. For surgeons who intend to become involved in its repair or reconstruction, it is mandatory to understand the full range of anatomic, physiologic, and diagnostic considerations prior to embarking upon a surgical course. Proper eyelid function depends upon the integrity of its constituent parts, including the margin, tarsus, muscle, and globe apposition. The lacrimal pump mechanism is produced by proper eyelid function and structure, and must be adequately assessed. The puncta and canaliculi are delicate structures and must be manipulated with care and gentleness. The lacrimal sac is a static structure that serves as a collecting sphere but also may be forced to evacuate its contents into the nasolacrimal duct by the "squeezing" action of the investing tendons. Proper tendon position must be maintained after surgery or trauma to facilitate this action. The nasolacrimal sac may be damaged after facial fractures or blocked from intranasal conditions. If the blockage cannot be relieved, it must be bypassed by performing a dacryocystorhinostomy. The use of long-term, indwelling silicone intubation catheters greatly facilitates the successful reconstruction of the lacrimal drainage system. Proper attention to all of these points will be appreciated by the patient.

Management of orbital trauma and foreign bodies.

Blunt and penetrating trauma to the orbital region can have a devastating effect both functionally and cosmetically for the orbit. Penetrating injuries to the orbit should be suspected whenever there is a history of trauma to the regions of the eyelids. Meticulous inspection of the eyelids and globe should be undertaken, and if there is any suspicion of a foreign body retained within the orbital soft tissues, then a CT scan should be obtained. It is possible that the foreign body is not opaque, and exploration of the soft tissues may be indicated. Blow-out fractures of the orbit should be explored and repaired when the evidence clearly indicates that a blow-out is present. This includes the clinical presence of diplopia, evidence of muscle entrapment with forced duction testing, and CT scan showing orbital wall fracture with explosion of the orbital contents into the paranasal sinuses. If these signs or symptoms are equivocable, then a waiting period of 10 to 14 days is indicated to rule out the presence of a nerve palsy, which should improve. However, a CT scan showing a large blow-out defect of the orbit should be repaired regardless of the clinical signs at the time because of the late sequelae of enophthalmos and hypophthalmos. It is very difficult to secondarily repair an orbit that is contracted owing to loss of volume from an orbital blow-out fracture. Procedures of this sort involve the reintroduction of autogenous fat into the orbital contents and are very difficult technically. Although orbital fractures should not be routinely explored, each should be viewed with its own merit and an aggressive approach developed if there is clinical evidence of a blow-out fracture.

Nasoethmoid complex injuries.

Blunt and penetrating trauma to the nasoethmoid complex can present a challenge to reconstruction by the facial trauma surgeon. Both functional and cosmetic problems exist with these injuries and both must be considered in the surgical plan. Adequate preoperative physical examination and roentgenologic evaluation, coupled with a thorough ophthalmologic consultation, are required for complete knowledge of the extent of the damage. The surgical repair of nasoethmoid fractures involving the medial canthal tendon and lacrimal drainage system should be repaired primarily. A medial blow-out fracture of the orbit is uncommon but should be considered in all cases of severe nasoethmoid complex fractures.

Research on remounting procedures.

This study has indicated that numerous benefits accrue from remounting dentures to correct occlusion and recontouring the tissue side of the bases at the time of insertion. This appears to be due to the changes in contour of the denture bases after the stone casts have been removed from them and indicates that a significant change in the occlusal relationship occurs during the deflasking procedure. Since adjustments and postinsertion complaints were materially decreased by early remounting and alteration, patients should benefit from such procedures by receiving restorations that may decrease the rate of bone resorption, be more comfortable, and tend to be effective for a longer period of time. The dentist should consequently be more satisfied knowing that he has done everything possible to provide quality dentistry to his patients.