[The effect of episiotomy on pelvic floor muscle function within six months after first childbirth through electromyography and questionnaires assessment]

Objective: To compare the impact of mediolateral episiotomy on pelvic floor muscle (PFM) function through surface electromyography (sEMG) and quality of life questionnaire assessment. Methods: From January 2018 to June 2019, 1 250 eligible primiparous women were enrolled in Beijing Hospital and the First People's Hospital of Yunnan Province. Participants were divided into episiotomy group (n=676)and non-episiotomy group (n=574). Both groups underwent clinical pelvic examination, sEMG assessment, and quality of life (QOL) questionnaire assessment at two fixed time points: 6-8 weeks, 6 months after vaginal delivery. Follow-up of sEMG amplitudes and their correlation with QOL questionnaire scores were evaluated. Results: Among the women delivered with episiotomy, the peak amplitude of phasic contraction (PPC) was (17.7±5.3) μV at 6-8 weeks after childbirth and (29.6±8.7) μV at 6 months after childbirth. The mean amplitude of tonic contraction (MTC) was (14.8±7.4) μV and (22.2±8.9) μV, respectively. In the non-episiotomy group, PPC was (20.0±7.9) μV and (35.4±10.7) μV at 6-8 weeks and 6 months, and MTC was (17.8±9.0) μV and (27.5±8.9) μV, respectively. Compared with EMG amplitudes at 6-8 weeks, both PPC and MTC significantly improved at 6 months in both groups (all P<0.01). Moreover, episiotomy was related with significantly lower PPC and MTC at both fixed checkups. Besides, both IIQ-7 and PFIQ-7 questionnaire scores improved at 6 months compared with those at 6-8 weeks in both groups (all P<0.001). There was consistently significant difference in QOL scores between episiotomy and non-episiotomy group at two checkups (all P<0.05). A negative correlation was observed between PFM contractile amplitudes and QOL scores at both time points after childbirth (all P<0.05), and the correlation weakened with time. Conclusion: Episiotomy has a negative impact on the postpartum PFM contractile function within 6 months after childbirth. The negative correlation between the sEMG and QOL scores indicates that sEMG is a candidate assessment for PFM function follow-up after childbirth.

Ultrasonography of fetal cleft lip and palate in first-trimester

PURPOSE OF INVESTIGATION

To explore the ultrasonographic methods towards cleft lip and palate (CLP) in first-trimester.

MATERIALS AND METHODS

3,795 fetuses were scanned for facial structures including cross section of upper alveolar process, oblique coronal section of upper lip, and postnasal triangle section when measuring nuchal translucency (NT). The abnormal cases underwent ultrasonography for clear diagnosis at 17-18 gestational weeks (GWs), while the negative cases underwent systemic ultrasonography at 20-26 GWs, and followed up until birth.

RESULTS

Among the 3795 fetuses, 16 cases had CLP, with an incidence rate as 4.2%; 12 were detected in first trimester, with a detection rate of 75%, and the detection rate of bilateral CLP was 100%, four were missed, with a misdiagnosis rate of 25%, and 12 cases examined at 17-18 GWs met first-trimester diagnosis. Among the four missed cases, two were diagnosed with systemic ultrasonography, and two were diagnosed postnatally. All cases were confirmed after induction of labor or after birth.

CONCLUSIONS

Ultrasonography in first-trimester could diagnose severe case of CLP.

[Analysis of Forensic Characteristics about 23 Family Homicide Cases]

OBJECTIVES

To provide references for forensic analysis of family homicides cases by analyzing the situations of scene, injuries and individual which were related to the family homicide cases in a county.

METHODS

The data of 23 family homicide cases from 2004 to 2013 were collected. The basic situation of individual involved, the relationship between dead and suspect, the cause of death, the motive, the location, time and tools of the crime and the behavior of the suspect after crime etc. were analyzed.

RESULTS

The characteristics of the 23 family homicides cases showed that couple relationship was the most common relationship; passion killing was the most common motive; local materials were mostly used as the tools for committing crimes; most crimes were committed in residences; most time of crime was night.

CONCLUSIONS

The analysis of family homicide cases should be based on the scene investigation, the examination of the body and combined with the investigation of the situation.

Sensitivity of rat temporalis muscle afferent fibers to peripheral N-methyl-D-aspartate receptor activation

The temporalis muscle is a common source of pain in headache and chronic craniofacial pain conditions such as temporomandibular disorders, which have an increased prevalence in women. The characteristics of slowly conducting temporalis afferent fibers have not been investigated. Therefore, the aim of the present study was to examine the characteristics of slowly conducting temporalis muscle afferent fibers and to determine whether these fibers are excited by activation of peripheral N-methyl-D-aspartate receptors. The response properties of a total of 117 temporalis afferent fibers were assessed in male and female rats. A majority of these fibers had high mechanical thresholds and slow conduction velocities (<10 m/s). The mechanical threshold of the temporalis afferent fibers was inversely correlated with afferent conduction velocity, however, no sex-related differences in mechanical threshold were identified. There were also no sex-related differences in N-methyl-D-aspartate-evoked afferent discharge. Indeed, injection of a high concentration (1600 mM) of N-methyl-D-aspartate into the temporalis muscle was necessary to evoke significant afferent discharge. Thirty minutes after the initial injection of N-methyl-D-aspartate into the temporalis muscle, a second injection of N-methyl-D-aspartate produced a response only about 50% as large as the initial injection. Co-injection of ketamine (20 mM) with the second injection of N-methyl-D-aspartate significantly decreased N-methyl-D-aspartate-evoked afferent discharge in both sexes. This concentration of ketamine is greater than that needed to attenuate afferent discharge evoked by injection of glutamate into the masseter muscle. These results suggest that unlike masseter afferent fibers, temporalis afferent fibers are relatively insensitive to peripheral N-methyl-D-aspartate receptor activation.

MRS assessment of glutamate clearance in a novel masticatory muscle pain model

The injection of 1.0 M glutamate into the masseter (jaw-closer) muscle results in a short period of muscle pain (5-10 min) and a prolonged period of mechanical sensitization (> 30 min). It is unclear, however, whether there is a temporal relationship between intramuscular glutamate concentration and either muscle pain or mechanical sensitization. In the present study, (1)H MRS and electrophysiological recording of masticatory muscle nerve fibers were performed in order to monitor glutamate clearance and nerve fiber activity, respectively, after injection of glutamate into rat masticatory muscles. Glutamate signal amplitude was found to decay rapidly (half-life t 1/2 = 108 +/- 42 s), and became indistinguishable from the baseline 10 min after the injection. Glutamate-evoked nerve fiber activity was also found to decay rapidly (t 1/2 = 76 +/- 28 s). These results suggest that glutamate clearance correlates well with the time course of glutamate-evoked muscle pain fiber discharge.

Stress distribution and failure mode of dental ceramic structures under Hertzian indentation

OBJECTIVES

To understand better the clinically-relevant failure of the ceramic in ceramic-cement-substrate structures under Hertzian indentation, including the effects of supporting substrate modulus and ceramic thickness on the stress distribution in the ceramic.

METHODS

Discs (thickness, T(c)=0.2, 0.6, 1.2, 1.6, 2.0, 2.4 mm) of a glass-ceramic material (IPS Empress 2, Ivoclar) were cemented (Variolink II, Vivadent) to flat polymer substrates with modulus of elasticity E(s) of 2, 6 and 10 GPa. The top surface of the ceramic-cement-substrate structure was loaded by a 20 mm radius spherical indenter until the initial failure of the ceramic occurred. The finite element method was used to analyse the stress distribution under such Hertzian indentation, varying E(s) and T(c), as well as calculating the maximum tensile stress based on the experimentally observed failure load and contact radius. The failure initiation site of the ceramic was identified by fractography using scanning electron microscopy.

RESULTS

The tensile stress concentration at the cementation surface of the ceramic was the predominant factor controlling the ceramic failure. Failure load increased with increase of E(s), while the maximum tensile stress at the cementation surface of the ceramic clearly decreased. Failure load increased logarithmically with ceramic thickness, but the critical tensile stress increased linearly.

SIGNIFICANCE

The failure mode observed clinically for ceramic restorations was reproduced in laboratory tests.

Fatigue crack propagation path across the dentinoenamel junction complex in human teeth

The human tooth structures should be understood clearly to improve clinically used restorative materials. The dentinoenamel junction (DEJ) plays a key role in resisting crack propagation in teeth. The aim of this study was to determine the fracture toughness of the enamel-DEJ-dentin complex and to investigate the influence of the DEJ on the fatigue crack propagation path across it by characterizing fatigue-fractured enamel-DEJ-dentin complexes using optical and scanning electron microscopy. The results of this study showed that the fracture toughness of the enamel-DEJ-dentin complex was 1.50 +/- 0.28 Mpa x m(1/2). Based on the results of this investigation, it was concluded that the DEJ complex played a critical role in resisting crack propagation from enamel into dentin. The DEJ complex is, approximately, a 100 to 150 microm broad region at the interface between enamel and dentin. The toughening mechanism of the DEJ complex may be explained by the fact that crack paths were deflected as cracks propagated across it. Understanding the mechanism of crack deflection could help in improving dentin-composite as well as ceramic-cement interfacial qualities with the aim to decrease the risk of clinical failure of restorations. Both can be viewed as being composed from a layer of material of high strength and hardness bonded to a softer but tougher substratum (dentin). The bonding agent or the luting cement layer may play the critical role of the DEJ in improving the strength of these restorations in clinical situations.

Analysis of prognosis and disease progression after local recurrence of melanoma

BACKGROUND

Local recurrence of melanoma is associated with a grave prognosis. However, the characteristics and the mode of disease progression for patients with local recurrence have not been adequately addressed in the literature.

METHODS

A retrospective analysis of patients treated at a single institution revealed a subset of patients (n = 648) with local recurrence of melanoma as a first event. Patient characteristics, histologic determinants, and disease free interval were variables used to identify prognostic factors.

RESULTS

In this group of patients, male gender (P = 0. 0163), increasing age (P = 0.0001), head and neck primaries (P = 0. 0001), thicker Breslow depths (P = 0.0022), deeper Clark levels (P = 0.0010), and ulceration of the primary tumor (P = 0.0348) suggested a shorter time until local recurrence. Breslow depth (P = 0.0004), Clark level (P = 0.0043), and ulceration (P = 0.0001) still factored into the survival prognosis after recurrence. Truncal primaries (P = 0.0005) and shorter disease free intervals (P = 0.0098) were also associated with poorer outcomes after recurrence. Of the 648 patients, 124 showed no progression, 196 developed another local recurrence, 178 developed in-transit/lymph node metastases, and 150 had systemic recurrences. Survival was only 33.6% for patients with further metastases, compared with 77.4% for patients with no progression of disease after a median follow-up of 38.9 months.

CONCLUSIONS

There was a 48.5% mortality rate at 5 years of follow-up after local recurrence. Long term survival (> 10 years) was estimated to be 34.9%. The patterns of failure after local recurrence suggest that patients may benefit from aggressive locoregional therapy.

MCA106 fibrosarcoma cells transduced with granulocyte/macrophage colony-stimulating factor are not superior to the wild-type cells in suppressing the growth of hepatic metastases

BACKGROUND AND OBJECTIVES

Vaccination with cytokine gene-modified tumor cells augments the immune response against established tumors and protects against tumor challenges. In this study, we investigated the vaccine potential of GM-CSF-transduced MCA106 fibrosarcoma (MCA-GMCSF) cells in the C57BL/6 (B6) murine hepatic metastasis model.

METHODS

Experimental mice received one to three weekly vaccines (subcutaneous/intramuscular, s.c./i.m.) of irradiated, parental, or GM-CSF-transduced MCA106 tumor cells. One week after the last immunization, hepatic metastases were established through the intrasplenic injection of live MCA106 parental (MCA106P) tumor cells. The animals were then sacrificed 3-4 weeks after surgery for evaluation of hepatic tumor burden.

RESULTS

Based on in vivo experiments, both GM-CSF-modified and parental MCA106 tumor cell vaccines induced strong protection against hepatic tumor growth with grossly visible tumors rarely identified. This protection was evident even at a single vaccine dose of as low as 1x10(5) irradiated cells. Unimmunized control mice, on the other hand, consistently developed substantial hepatic tumors. Cytotoxicity assays on splenocytes (cultured in vitro for 4-5 days) showed that both groups of vaccinated mice developed strong tumor-specific cytotoxic T-lymphocyte (CTL) responses. Immunohistochemical analysis of injection sites showed infiltration of dendritic cells (DCs) and macrophages into subcutaneously injected MCA-GMCSF cells. Mostly macrophages, however, were seen at the injection site of MCA106P cells. Furthermore, the MCA106P cells expressed high levels of MHC class I antigens and the level of expression was not significantly altered by transduction with the GM-CSF gene. The high expression of MHC class I antigens probably contributed to the strong immunogenicity of the MCA106P cell vaccine.

CONCLUSIONS

This study demonstrates that MCA106 parental cells are as effective as the GM-CSF-transduced cells in suppressing the growth of hepatic metastases. The cellular immune responses induced by these two vaccines, however, are probably mediated by different subsets of host effector cells. These results have important implications for the use of GM-CSF-transduced cell vaccines in the immunotherapy of tumors that have the propensity to metastasize through the lymphatic channels and the circulatory system.

Melanoma of the gallbladder: a review of cases seen at Duke University Medical Center

BACKGROUND

Both primary and metastatic melanoma of the gallbladder are rare. In cases involving isolated tumors of the gallbladder, there continues to be controversy regarding the establishment of primary status. Despite appropriate therapy, the diagnosis of either condition portends a poor prognosis, with few patients surviving more than 2 years.

METHODS

A review of all patients seen at Duke University Medical Center since 1970 generated 1 case of primary and 19 cases of secondary melanoma of the gallbladder. These were analyzed with respect to presentation, clinical and pathologic diagnosis, treatment, and prognosis.

RESULTS

The sole patient with a primary lesion presented with acute cholecystitis. Ultrasound demonstrated a mass in the lumen of the gallbladder. Cholecystectomy revealed melanoma, and the patient eventually died of disseminated disease 13.5 months later. Survival was poor for patients who presented with metastases to the gallbladder in the setting of widespread disease, with 0% survival at 1 year (n=11). Those with isolated, resectable lesions fared better overall, with 100% survival (n=6) at 1 year. One patient remains alive and free of disease 13.8 years later, which, to our knowledge, represents the longest documented survival for a patient with melanoma that has metastasized to the gallbladder.

CONCLUSIONS

Surgery remains the mainstay of therapy for patients with gallbladder melanoma and appears to improve patient outcome in the setting of resectable disease. Hopefully, further investigations will lead to standardized protocols for the treatment of these lesions.

Human dendritic cells, pulsed with either melanoma tumor cell lysates or the gp100 peptide(280-288), induce pairs of T-cell cultures with similar phenotype and lytic activity

Dendritic cells (DCs) pulsed with unfractionated tumor cell lysates or defined tumor peptides provide potent vaccines which elicit strong antitumor immunity. In this study, we generated DCs from the 2-h adherent progenitor cells obtained from the peripheral blood of melanoma patients. These DCs were able to capture biotinylated melanoma tumor cell lysates. We examined the efficacy of immunogens composed of DCs loaded either with the melanoma peptide gp100 [amino acids 280-288 (DC/gp100)] or with lysates from melanoma tumor cells (DC/lysates) in inducing cytotoxic T-cells from autologous PBLs of HLA-A2 melanoma patients. After four to five weekly stimulations of bulk PBLs with DC/gp100 or DC/lysates, the cultures were enriched with CD3+ T-cells and exhibited one of three phenotypic and functional patterns: (1) Predominant expression of CD8+ and MHC class I-restricted CTLs which displayed strong lytic activity against melanoma cells and T2 cells loaded with the gp100 peptide, (2) mixed CD4+/CD8+ phenotype and weak lytic activity, or (3) nonlytic and predominantly CD4+ cultures. Interestingly, T-cell cultures from each patient exhibited similar phenotypes and lytic activities whether the stimulant was DC/gp100 or DC/cell lysates. Our study demonstrates that DCs pulsed with soluble melanoma peptides or cell lysates are capable of inducing CD8+ CTLs from autologous PBLs of some, but not all, melanoma patients. The function and phenotype of the generated T-cell cultures are governed by DCs since both antigens (the gp100 peptide and melanoma lysates), when presented by a given DC preparation, induced similar T-cell cultures. In summary, it may be difficult to predict the nature of the cellular responses elicited by DC/tumor antigen vaccines from patient to patient.