Abnormal Vaginal Cytology after Total Laparoscopic Hysterectomy in Patients with Cervical Intraepithelial Neoplasia.

To explore the incidence of abnormal vaginal cytology after total laparoscopic hysterectomy for the treatment of cervical intraepithelial neoplasia 3, we retrospectively analyzed the medical records of patients treated at NHO Shikoku Cancer Center (Japan) in 2014-2019. The cases of 99 patients who underwent a laparoscopic (n=36) or open (n=63) hysterectomy and postoperative follow-up were examined. Abnormal vaginal cytology was detected in 13.9% (5/36) of the laparoscopic-surgery (LS) group and 14.3% (9/63) of the open-surgery (OS) group. A vaginal biopsy was performed at the physicians' discretion; one LS patient and six OS patients were diagnosed with vaginal intraepithelial neoplasia. The cumulative incidence of abnormal vaginal cytology at 3 years post-hysterectomy was 21.4% (LS group) and 20.5% (OS group), a nonsignificant difference. A multivariate analysis showed that age > 50 years was the only independent risk factor for abnormal vaginal cytology among the covariates examined including age; body mass index; histories of vaginal delivery, abdominal surgery, and smoking; and surgical approach (hazard ratio 8.11; 95% confidence interval 1.73-37.98; p=0.01). These results suggest that the occurrence of abnormal vaginal cytology after a hysterectomy may not be influenced by the laparoscopic procedure but is associated with older age.

Exploring Indicators of Subcutaneous Tissue Fluid Accumulation in Breast Cancer-Related Lymphedema Patients Using Fractal Analysis with Virtual Volume.

Background: Breast cancer treatment sometimes causes a chronic swelling of the arm called breast cancer-related lymphedema (BCRL). Its progression is believed to be irreversible and is accompanied by tissue fibrosis and lipidosis, so preventing lymphedema from progressing by appropriate intervention at the site of fluid accumulation at an early stage is crucial. The tissue structure can be evaluated in real time by ultrasonography, and this study aims at assessing the ability of fractal analysis using virtual volume in detecting fluid accumulation within BCRL subcutaneous tissue via ultrasound imaging. Methods and Results: We worked with 21 women who developed BCRL (International Society of Lymphology stage II) after unilateral breast cancer treatment. Their subcutaneous tissues were scanned with an ultrasound system (Sonosite Edge II; Sonosite, Inc., FUJIFILM) using a 6- to 15-MHz linear transducer. Then, a 3-Tesla MR system was used to confirm fluid accumulation in the corresponding area of the ultrasound system. Significant differences in both H + 2 and complexity were observed among the three groups (with hyperintense area, without hyperintense area, and unaffected side) (p < 0.05). Post hoc analysis (Mann-Whitney U test; Bonferroni correction p < 0.0167) revealed a significant difference for "complexity." The evaluation of the distribution in Euclidean space showed that the variation of the distribution decreased in the order of unaffected, without hyperintense area, and with hyperintense area. Conclusion: The "complexity" of the fractal using virtual volume seems to be an effective indicator of the presence or absence of subcutaneous tissue fluid accumulation in BCRL.

A Pilot Study of Determining the Reliability of a New Three-Dimensional Scanning System for Measuring Truncal Thickness After Breast Cancer Surgery.

Background: Lymphedema often affects the trunk after breast cancer surgery. Measuring volume baseline can help detect lymphedema-related changes early, thereby allowing for early intervention efforts. However, there is no quantitative method for detecting truncal lymphedema. As a preliminary investigation into the development of a new method for measuring truncal lymphedema, this study aimed to investigate the reliability and define the minimal detectable change (MDC) in posterior truncal thickness using a three-dimensional (3D) scanning system. Methods and Results: This observational study included 21 women who had undergone a mastectomy for breast cancer. The 3D images of every subject's trunk were captured by a handheld 3D scanner at two time points. The acquired 3D images were used to calculate the differences in thickness between the affected and unaffected sides at eight points on the trunk. The reliability was determined by checking for agreement between the trials (intraclass correlation coefficient) and by investigating the presence of systematic bias between the measurement error and true value (Bland-Altman analysis). Then, the MDC was calculated. For 14 of the 21 participants, 3D images without missing data at both time points were obtained. Analysis indicated that there was no systematic bias regarding the mean value at the seven body points. Fair-to-excellent reliability was shown at the five points in the middle of the trunk (MDC: 4.14-9.79 mm). The other three points (at the top and bottom of the trunk) had limited reliability. Conclusions: The 3D scanning system effectively measured the differences in thickness between the affected and unaffected sides of participants' posterior trunks, with fair-to-excellent reliability in the middle of the trunk.

Prediction of the Presence of Fluid Accumulation in the Subcutaneous Tissue in BCRL Using Texture Analysis of Ultrasound Images.

Background: Breast cancer-related lymphedema (BCRL) is a chronic swelling of the arm due to breast cancer treatment. Lymphedema is diagnosed and staged on the basis of limb circumference measurements and the patient's subjective symptoms, which have poor reproducibility and objectivity: these cannot detect any fluid accumulation in the tissue. Ultrasonography is a feasible noninvasive technique that can be used to evaluate tissue structure in real time. This study aimed to assess the ability of texture features for discriminating the presence of accumulated fluid within the subcutaneous tissue of BCRL using ultrasound (US) imaging. Methods and Results: This study included 20 women who were treated for unilateral breast cancer and who subsequently developed BCRL (International Society of Lymphology stage II). Subcutaneous tissue was scanned through an US system (Sonosite Edge II; Sonosite, Inc., FUJIFILM) using a 6- to 15-MHz linear transducer to assess the ability of texture features for discriminating the presence of accumulated fluid within the subcutaneous tissue of BCRL. Fluid accumulation was observed using a 3-Tesla MR system under double-echo steady-state conditions. There was a significant difference among the three groups (with hyperintense area, without hyperintense area, and unaffected side) in 11 of 14 textural features (p < 0.05). Post hoc analysis (Mann-Whitney U test; Bonferroni correction p < 0.0167) revealed significant differences in seven textural features within the hyperintense area. Conclusions: This study revealed that seven texture features quantified by US imaging data can provide information regarding fluid accumulation in the subcutaneous tissue of lymphedema.

Correlation of World Health Organization 2010 Classification for Gastroenteropancreatic Neuroendocrine Neoplasms with the Prognosis of Ovarian Neuroendocrine Neoplasms: Kansai Clinical Oncology Group-Protocol Review Committee/Intergroup Study.

BACKGROUND: In 2014, the World Health Organization (WHO) released a classification system introducing neuroendocrine neoplasms (NENs) of the female reproductive tract, excluding the ovaries. This study aimed to evaluate whether retrospective adaption of the gastroenteropancreatic (GEP)-NEN classification is feasible for ovarian NENs (O-NENs) and correlates with prognosis. METHODS: Sixty-eight patients diagnosed with carcinoid, small cell carcinoma (pulmonary type), paraganglioma, non-small/large cell neuroendocrine carcinoma (NEC), mixed NEC, or undifferentiated carcinomas at 20 institutions in Japan were included in this retrospective cross-sectional study. We identified O-NENs through central pathological review using a common slide set, followed by reclassification according to WHO 2010 guidelines for GEP-NENs. A proportional hazards model was used to assess the association of prognostic factors (age, stage, performance status, histology, and residual disease) with overall survival (OS) and progression-free survival (PFS). RESULTS: Of the 68 enrolled patients, 48 were eligible for analysis. All carcinoids (n = 32) were reclassified as NET G1/G2, whereas 14 of 16 carcinomas were reclassified as NEC/mixed adeno-NEC (MANEC) (Fisher's exact test; p < 0.01). The OS/PFS was 49.0/42.5 months and 6.5/3.9 months for NET G1/G2 and NEC/MANEC, respectively. Histology revealed that NEC/MANEC was associated with increased risk of death (HR = 48.0; 95% CI, 3.93-586; p < 0.01) and disease progression (HR = 51.6; 95% CI, 5.54-480; p < 0.01). CONCLUSION: Retrospective adaption of GEP-NEN classification to O-NENs is feasible and correlates well with the prognosis of O-NENs. This classification could be introduced for ovarian tumors.

The Correlation Between Fluid Distribution and Swelling or Subjective Symptoms of the Trunk in Lymphedema Patients: A Preliminary Observational Study.

Background: Manual lymph drainage (MLD) is one of the common treatments for breast cancer-related lymphedema (BCRL). Although the primary goal of MLD is to drain the excessive fluid accumulated in the affected upper limb and trunk to an area of the body that drains usually, the use of MLD is decided based on swelling and subjective symptoms, without assessing whether there is fluid accumulated in the affected region. The purpose of this study was to examine truncal fluid distribution in a sample of BCRL patients and investigate any correlation between such fluid distribution and swelling or subjective symptoms. Methods and Results: An observational study was conducted with 13 women who had unilateral, upper extremity BCRL. Fluid distribution was evaluated by using two magnetic resonance imaging (MRI) sequences: half-Fourier acquisition single-shot turbo spin echo and three-dimensional double-echo steady-state. The presence of swelling was determined by lymphedema therapists, and subjective symptoms were measured by using a visual analog scale. On MRI, no participants had any free water signals in the trunk. However, seven had swelling and all 13 had some kind of subjective symptoms on the affected side of their trunk. Conclusions: These results suggest that swelling and subjective symptoms do not correlate with the presence of truncal fluid. For such cases, a different approach than MLD may be needed to address truncal swelling and related subjective symptoms. Checking for the presence of fluid in the truncal region may help MLD be used more appropriately.

Clinicopathologic features, treatment, prognosis and prognostic factors of neuroendocrine carcinoma of the endometrium: a retrospective analysis of 42 cases from the Kansai Clinical Oncology Group/Intergroup study in Japan.

OBJECTIVE: We conducted a retrospective, multi-institutional, collaborative study to accumulate cases of neuroendocrine carcinoma of the endometrium, to clarify its clinicopathologic features, treatment, prognosis and prognostic factors to collate findings to establish future individualized treatment regimens. To our knowledge, this is the largest case study and the first study to statistically analyze the prognosis of this disease. METHODS: At medical institutions participating in the Kansai Clinical Oncology Group/Intergroup, cases diagnosed at a central pathologic review as neuroendocrine carcinoma of the endometrium between 1995 and 2014 were enrolled. We retrospectively analyzed the clinicopathologic features, treatment, prognosis and prognostic factors of this disease. RESULTS: A total of 65 cases were registered from 18 medical institutions in Japan. Of these, 42 (64.6%) cases were diagnosed as neuroendocrine carcinoma of the endometrium based on the central pathological review and thus included in the study. Advanced International Federation of Gynecology and Obstetrics stages (stage III and IV) and pure type small cell neuroendocrine carcinoma cases had a significantly worse prognosis. Upon multivariate analysis, only histologic subtypes and surgery were significant prognostic factors. Pure type cases had a significantly worse prognosis compared to mixed type cases and complete surgery cases had a significantly better prognosis compared to cases with no or incomplete surgery. CONCLUSION: Our findings suggest that complete surgery improves the prognosis of neuroendocrine carcinoma of the endometrium. Even among cases with advanced disease stages, if complete surgery is expected to be achieved, clinicians should consider curative surgery to improve the prognosis of neuroendocrine carcinoma of the endometrium.

Uterine leiomyosarcoma well-controlled with eribulin mesylate.

Uterine leiomyosarcoma is a rare type of malignant gynecological tumor and has a poor prognosis; therefore, this tumor is often difficult to treat. Some new drugs have been approved during the past several years in Japan and are expected to be efficacious. Eribulin, one of these drugs, is a natural product of halichondrin B, which is isolated from a marine sponge. A recent clinical trial comparing eribulin with dacarbazine to target liposarcoma and leiomyosarcoma indicated that overall survival (OS) was prolonged by treatment with eribulin. We report a case of uterine progressive leiomyosarcoma that responded to eribulin. A 57-year-old woman was suspected of having leiomyosarcoma based on an endometrial biopsy and imaging examinations. Although the tumor grew toward the uterine artery on the right side of the uterine cervix, we performed a total abdominal hysterectomy and bilateral salpingo-oophorectomy to obtain an outcome of no gross residual disease. However, the margin of the right side of the uterine cervix was histologically positive, so leiomyosarcoma stage IIB (pT2bcN0cM0, FIGO2008) was diagnosed. Gemcitabine and docetaxel therapy was administered postoperatively. However, after three cycles, the residual tumor progressed. Other anticancer drugs were administered but were ineffective. We administered eribulin (1.4 mg/m2) as a fourth-line regimen, and the mass decreased by 32% after four cycles. However, the residual tumor continued to grow after eight cycles. The only adverse event associated with eribulin treatment was mild, grade 2 neutropenia. For our patient, eribulin was effective for her recurrent leiomyosarcoma. In selecting chemotherapy, there are currently no fixed guidelines; we should consider the characteristics and adverse events associated with each drug and patient performance status and comorbidities. In this patient, eribulin was associated with few adverse events, an easy route of administration and a good quality of life. Therefore, eribulin is expected to be efficacious for the treatment of gynecologic sarcoma.

Lynch syndrome-associated endometrial carcinoma with MLH1 germline mutation and MLH1 promoter hypermethylation: a case report and literature review.

BACKGROUND: Lynch syndrome is an autosomal dominant inherited disease caused by germline mutations in mismatch repair genes. Analysis for microsatellite instability (MSI) and immunohistochemistry (IHC) of protein expressions of disease-associated genes is used to screen for Lynch syndrome in endometrial cancer patients. When losses of both MLH1 and PMS2 proteins are observed by IHC, MLH1 promoter methylation analysis is conducted to distinguish Lynch syndrome-associated endometrial cancer from sporadic cancer. CASE PRESENTATION: Here we report a woman who developed endometrial cancer at the age of 49 years. She had a family history of colorectal cancer (first-degree relative aged 52 years) and stomach cancer (second-degree relative with the age of onset unknown). No other family history was present, and she failed to meet the Amsterdam II criteria for the diagnosis of Lynch syndrome. Losses of MLH1 and PMS2, but not MSH2 and MSH6, proteins were observed by IHC in endometrial cancer tissues. Because MLH1 promoter hypermethylation was detected in endometrial cancer tissue samples, the epigenetic silencing of MLH1 was suspected as the cause of the protein loss. However, because of the early onset of endometrial cancer and the positive family history, a diagnosis of Lynch syndrome was also suspected. Therefore, we provided her with genetic counseling. After obtaining her consent, MLH1 promoter methylation testing and genetic testing of peripheral blood were performed. MLH1 promoter methylation was not observed in peripheral blood. However, genetic testing revealed a large deletion of exon 5 in MLH1; thus, we diagnosed the presence of Lynch syndrome. CONCLUSIONS: Both MLH1 germline mutation and MLH1 promoter hypermethylation may be observed in endometrial cancer. Therefore, even if MLH1 promoter hypermethylation is detected, a diagnosis of Lynch syndrome cannot be excluded.

Long-term outcomes of postoperative taxane/platinum chemotherapy for early stage cervical cancer: a retrospective study.

BACKGROUND: Taxane/platinum (TP)-based combination chemotherapy is standard for the treatment of metastatic or recurrent cervical cancer. The aim of this study was to investigate the efficacy of postoperative TP therapy in early stage cervical cancer. METHODS: A retrospective review of patients with FIGO IB-IIB stage cervical cancer who were treated with radical hysterectomy and displayed surgical-pathological risk factors was performed. 122 patients were identified between 2003 and 2012. Survival was analyzed by Kaplan-Meier method and compared by the log-rank test. The Cox proportional hazards model was used to investigate predictors of survival. RESULTS: The median follow-up period was 82.4 months. The postoperative adjuvant therapy was TP in 82 (67.2%) patients, other chemotherapies in 10 (8.2%), radiotherapy (RT) in 25 (20.5%), and no further therapy (NFT) in 5 (4.1%). Survival was analyzed using 4 subgroups according to the postoperative adjuvant therapy. The estimated 5-year overall survival was 95.1% in the TP group, 90.0% in the other chemotherapy group, 78.9% in the RT group, and 100% in the NFT group. No significant difference of survival was observed in the subgroups. However, when analyzing only patients who displayed high-risk factors, non-TP adjuvant therapy (including RT and other chemotherapies) was independently associated with shorter survival on multivariate analysis. In the TP group, multivariate analysis revealed that a positive surgical margin was a significant predictor of shorter survival. CONCLUSIONS: Postoperative TP is effective in patients with surgically treated early stage cervical cancer. In these populations, a positive surgical margin could be associated with poor prognosis.

Lower-limb warming improves sleep quality in elderly people living in nursing homes.

Sleep disturbances are common in older people. This study was conducted to examine the effects of a hot pack, which was used to warm the lower limbs, on the sleep of elderly people living in a nursing home. This is a prospective cohort involving seven elderly women. Subjects aged 74-93 years old were treated by warming the lower limbs for 40 minutes using hot packs every night over 8 weeks. A hot pack made of a dense polymer and warmed in a microwave oven was used as a warming device. In the first and last week, the subjects were required to wear an activity monitor to determine their sleep-awake status. During the second to ninth week, they received limb-warming treatment by a hot pack heated to 42ºC for 40 min every night. Surface skin temperature data were collected by thermographic measurement. As a result, lower-limb warming by a hot pack significantly improved the quality of sleep in the subjects. During warming, the surface temperature of the hands and face rose by approximately 0.5-1.5ºC. This study showed that lower-limb warming with a hot pack reduced sleep latency and wake episodes after sleep onset; thus, improving the quality of sleep in elderly people living in a nursing home.

[Safety and Efficacy of Cisplatin Treatment after Carboplatin Hypersensitivity Reactions in Gynecologic Malignancies].

To investigate the safety and efficacy of cisplatin(CDDP)treatment after carboplatin(CBDCA)hypersensitivity reactions (CHSR)in gynecologic malignancies, we retrospectively reviewed the clinical records of 544 patients who underwent paclitaxel and CBDCA therapy(TC therapy). CHSR was observed in 18 patients. Eight patients were administered weekly paclitaxel and CDDP therapy(wTP therapy)continuously, to confirm that there was no CDDP hypersensitivity followingintravenous administration of 10 mgCDDP. At the onset of CHSR, the patients had received a median of 9 TC therapy cycles, and the median number of CBDCA administrations was 14. The frequency of CHSR was significantly higher in patients who received 7 cycles or more of TC therapy and CBDCA administration(p<0.0001). The median number of wTP therapy administrations was 8. Although CDDP hypersensitivity reactions were observed in 2 patients, their symptoms were mild(Grade 2, CTCAE v4.0). Of the 6 patients who received wTP therapy and had evaluable disease sites, 1, 2, 2 and 1 patients showed CR, PR, SD, and PD, respectively. The median progression-free survival in these 6 patients was 9.5 months. For patients with the platinum- sensitive disease who have CHSR, CDDP could improve their prognosis.

Passive ankle movement increases cerebral blood oxygenation in the elderly: an experimental study.

BACKGROUND: Ankle exercise has been proven to be an effective intervention to increase venous velocity. However, the efficacy of ankle exercise for improving cerebral circulation has not been determined. We hypothesized that ankle exercise in the supine position would be able to increase oxyhemoglobin levels measured at the forehead. METHODS: Seventeen community-dwelling elderly women participated in this study. We recorded blood pressure, heart rate (HR), and oxyhemoglobin (OxyHb) levels from the participants in the supine position. Participants repeated ankle plantar flexion and dorsiflexion movements for 1 min. Two types of exercise were used: active movement and passive movement. We used two-way analysis of variance to assess the differences in mean arterial blood pressure (MAP), HR, and OxyHb between different exercises (active and passive) and times (before and after exercise). RESULTS: The HR and MAP increased during active exercise but not during passive exercise. On the other hand, the levels of OxyHb measured at the forehead were elevated during both active and passive exercises. This increase lasted at least 1 min after exercise. There was no significant difference between active and passive exercise with regard to OxyHb; however, a significant difference was observed between before and after exercise (p < 0.05, η(2) G = 0.153). CONCLUSIONS: The physiological response of OxyHb to ankle exercise was different from that of the other cardiovascular functions. Both active and passive ankle exercises were able to increase cerebral blood oxygenation, whereas the other cardiovascular functions did not respond to passive exercise.

Relationship between admission day and timing of surgery for patients with hip fracture.

AIM: This study investigated: (i) the relationship between admission day of the week and the timing of surgery; (ii) whether the admission day of the week predicted length of stay or patients' outcomes; and (iii) the relationship between the timing of surgery and mortality. METHODS: This was a retrospective, observational study of two community general hospitals in Japan. The inclusion criteria were patients aged 65 years or older who had experienced a hip fracture and undergone surgery during April 2007 to March 2011. Data on demographics, care processes, and health outcomes during hospital stays were collected from hospital records. A questionnaire was sent to patients and/or their family members about the patients' health outcomes after discharge from hospital for hip fracture surgery. RESULTS: Data were collected from a total of 714 patients. In both hospitals, orthopedic surgery was not scheduled every day, and the admission day was significantly related to the timing of surgery. In hospital 1, the admission day explained 38.1% of the variance in the timing of surgery, and in hospital 2, it explained 8.3%. The admission day with early surgery predicted an early discharge. The admission day with delayed surgery predicted better survival. There was no significant relationship between the timing of surgery and mortality in either hospital. CONCLUSION: Earlier surgery, by daily operations, may reduce the length of hospital stays, but its effect on patient outcome remains unclear. It is necessary to carefully determine which patients will benefit from earlier surgery.

Efficacy of complete decongestive therapy (CDT) on edematous rat limb after lymphadenectomy demonstrated by real time lymphatic fluid tracing.

Although complete decongestive therapy (CDT) is considered to reduce the volume of lymphedema, there is no concrete evidence to sustain its efficacy. The purpose of the present study was to find new evidence of CDT based on visualizing the changes of lymph fluid accumulating in an edematous limb using indocyanine green (ICG) fluorescent lymphography in real time.Twelve lymphedema rats were divided randomly into two groups. On the first day, ICG was injected into an edematous limb of rats, and no-intervention and CDT was applied to groups 1 and 2, respectively, for two weeks. ICG lymphography and circumferential measurements were done every two days in each two-week observation. The results indicates that a fluorescent flow to the ipsilateral axillary fossa was identified in all rats. In addition, network-like and dermal backflow patterns were observed in the lower legs and thighs. While manual lymph drainage was applied in the CDT group, the flow moved more rapidly through this pathway than that in the no-intervention group. An area of high-intensity fluorescent signals concentrated around the injection sites diminished in the CDT group more than that in the no-intervention-group after two weeks. Circumferential lengths of the edematous limbs were longer than the non-edematous limbs in both groups 1 and 2 on the day of ICG injection. The no-intervention group 1 showed no significance differences during 14 days, whereas the CDT group 2 exhibited very significant differences. These results suggest that CDT has beneficial effects in lymphedema treatment.

Possibility of using nerve segments dissected from human cadavers for grafting: preliminary report.

An intercostal nerve obtained from a human cadaver 6 h post-mortem was transplanted into the rat sciatic nerve and nerve regeneration was observed 4 and 8 weeks after surgery. Sciatic nerves from deceased rats up to 2 days post-mortem were also transplanted for comparison. Good nerve regeneration was observed through the human cadaver-derived graft to the distal segment at the medial plantal nerve 8 weeks after surgery. The results of the present study indicate the possibility that nerves from human cadavers can be used for nerve grafting in clinical applications.

Poly lactic acid--caprolactone copolymer tube with a denatured skeletal muscle segment inside as a guide for peripheral nerve regeneration: a morphological and electrophysiological evaluation of the regenerated nerves.

A biodegradable copolymer of poly L-lactic acid and epsilon-caprolactone (PLAC) was manufactured into a tube, in which a denatured skeletal muscle segment was placed longitudinally. This model tube was implanted as a guide to promote nerve regeneration across a 5 cm gap in the rabbit sciatic nerve. Five months after implantation, good nerve regeneration was found throughout the graft and in the distal host nerve. The population (29.6/16 x 10(2) microm(2)) of regenerated nerves in the graft was higher than that of the contralateral normal sciatic nerve (18.0/16 x 10(2) microm(2)). Regenerated nerve fibers extended to the distal host nerve. The number of myelinated fibers was 13.7/16 x 10(2) microm(2) at a level 1.5 cm from the distal suture. The diameters (below 2 microm) of most regenerated myelinated (nerves in the graft and in the distal host nerve were much smaller than those (6-8 microm) of normal nerves. Electrophysiological evaluation showed that the hindlimb muscle (gastrocnemius) was innervated by motor nerves in all animals 5 months after implantation. These results indicate that the PLAC tube with a denatured muscle segment inside provided good conditions for nerve fiber regrowth. The PLAC tube is thought to protect the denatured muscle segment from rapid dissociation in the host tissue.

Extracellular matrix of human amnion manufactured into tubes as conduits for peripheral nerve regeneration.

The human amnion consists of the epithelial cell layer and underlying connective tissue. After removing the epithelial cells, the resulting acellular connective tissue matrix was manufactured into thin dry sheets called amnion matrix sheets. The sheets were further processed into tubes, amnion matrix tubes (AMTs), of varying diameters, with the walls of varying numbers of amnion matrix sheets with or without a gelatin coating. The AMTs were implanted into rat sciatic nerves. Regenerating nerves extended in bundles through tubes of 1-2 mm in diameter and further elongated into host distal nerves 1-3 weeks after implantation. Morphometrical analysis of the regenerated nerve cable at the middle of each amnion matrix tube 3 weeks after implantation was performed. The average numbers of myelinated axons were almost the same (ca. 80-112/10(4) microm(2)) in AMTs of 1-2 mm in diameter, as in the normal sciatic nerve (ca. 95/10(4) microm(2)). No myelinated fibers were found in AMTs composed of multiple thin tubes of 0.2 mm in diameter. The myelinated axons were thinner in implanted tubes than those in the normal sciatic nerve. The rate of occurrences of myelinated axons less than 4 microm in diameter was significantly higher in the AMTs, whereas axons in the normal sciatic nerve were diverse in distribution, with the highest population at 8-12 microm in diameter. Reinnervation to the gastrocnemius muscle was demonstrated electrophysiologically 9 months after implantation. It was concluded that the extracellular matrix sheet from the human amnion is an effective conduit material for peripheral nerve regeneration.

Comparison of the axonal and glial reactions between the caudal and rostral border in the cryoinjured dorsal funiculus of the rat spinal cord.

Axonal and glial reactions to traumatic injury were compared between the caudal and rostral border of the lesion after freeze-injury to the C3 dorsal funiculus by attaching a liquid nitrogen-cooled copper probe to the dorsum of the rat spinal cord. The axonal and glial changes were examined up to 60 days postoperative by light and electron microscopy and immunohistochemistry for neurofilaments. Regenerative axonal changes and the appearance of numerous undifferentiated cells were found at the caudal border 7 days after cryoinjury. In contrast, such axonal and cellular reactions were scarce at the rostral border. Undifferentiated cells clearly manifested their phenotypes by differentiating into oligodendrocytes or astrocytes 11 days postinjury. The results indicated that glial cell reactions occurred in association with regenerative axonal changes at the proximal stump of the injured nerve fibers, suggesting that regenerating and demyelinated naked axons could be responsible for the appearance of the immature glial cells.