P1038Device implantation after catheter ablation of paroxysmal atrial fibrillation with coexisting sick sinus syndrome: Insights from the Kansai Plus Atrial Fibrillation (KPAF) study

Background

Sick sinus syndrome (SSS) and atrial fibrillation (AF) frequently coexist and interact to initiate and perpetuate each other. Several retrospective or small cohort studies have suggested that successful catheter ablation of AF may help to waive device implantations in patients with paroxysmal AF plus SSS, however, no prospective large studies are so far available on this scenario.

Purpose

We aimed to elucidate the device implantation-free survival after catheter ablation of paroxysmal AF with coexisting SSS in a prospective large-scale registry. We also determined the risk factors for device implantations after catheter ablation of paroxysmal AF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) study is a multi-center prospective registry that enrolled 5,019 consecutive patients that underwent an initial pulmonary vein isolation-based radiofrequency catheter ablation of AF. This study was comprised of 3,226 patients with paroxysmal AF registered in the KPAF study (age, 64.8±10.5 years old; female, n=999 [31.0%]; left atrial diameter [LAD], 37.5±8.0 mm; left ventricular ejection fraction [LVEF], 65.3±8.4%, CHADS2 score, 1.09±1.05). The atrial tachyarrhythmia-free and device-free survivals after catheter ablation were compared between patients with SSS (n=368; tachy-brady syndrome, 88%) and without SSS (control; n=2,858).

Results

The atrial tachyarrhythmia-free survival was almost identical between the two groups both after the first ablation session (Fig.1A) and after the last procedure with an average of 1.3±0.5 sessions. At baseline, the devices had already been implanted in 53 (14.4%) SSS and 36 (1.3%) control patients. In the remaining patients, devices were newly implanted in 54 (17.1%) SSS and 62 (2.2%) control patients during the follow-up of 3 years after the catheter ablation (Figure 1B). In the SSS group, devices were implanted predominantly within 6 months after the catheter ablation, and atrial tachyarrhythmia recurrence preceded the device implantation in 48 (89%) patients. Multivariate predictors of device implantations after the paroxysmal AF ablation included: SSS (hazard ratio [HR] 6.85, 95% confidence interval [CI] 4.61–10.19, p<0.001), an age>75 years old (HR 1.69, 95% CI 1.08–2.64, p=0.019), a female gender (HR 2.16, 95% CI 1.44–3.24, p<0.001), the LAD (mm) (HR 1.05, 95% CI 1.02–1.08, p=0.006), and the LVEF (%) (95% CI 0.96, 95% CI 0.94–0.98, p<0.001).

Figure 1

Conclusions

Device implantations could be waived in >80% of patients with SSS at 3 years of follow-up after the catheter ablation of paroxysmal AF in this real world all comer prospective registry. In addition to coexisting SSS, predictors of device implantations after paroxysmal AF ablation included: the elderly, a female gender, a large LA, and a reduced LVEF.

Acknowledgement/Funding

None

65 THE EFFECTS OF CUMULUS CELLS ON DEVELOPMENTAL RATES OF VITRIFIED MOUSE OOCYTES IN C57BL/6J STRAIN

Unfertilized oocytes are one of the most desired germ-cell stages for cryopreservation because these cryopreserved oocytes can be used for assisted reproductive technologies, including IVF and intracytoplasmic sperm injection. However, in general, the fertility and developmental ability of cryopreserved oocytes are still low. We have recently reported that, in the presence of surrounding cumulus cells, matured mouse oocytes vitrified using calcium-free media and ethylene glycol retain their developmental competence (Kohaya et al. 2011 J. Reprod. Dev. 57, 675–680). Since the previous study was carried out using ICR mice (closed colony), we examined whether our protocol can be applied for C57BL/6J mice (inbred strain), which are commonly used for production of transgenic and knockout mice. The effect of cumulus cells on the ability of C57BL/6J mouse oocytes to be fertilized and develop in vitro was examined. Cumulus oocyte complexes (COC) derived from female mice with super ovulation were collected by flushing. Cumulus cells were removed for a portion of the oocytes (DO) using hyarulonidase. Oocytes from both treatment groups (COC and DO) were then vitrified according to the protocol we previously reported (Kohaya et al. 2011). After warming, vitrified COC and DO were used for IVF. All percentage data were subjected to arcsine transformation before statistical analysis. Data were analyzed by one-way ANOVA and Tukey’s test. Significance was considered at P < 0.05. The pronuclear formation rate of vitrified DO after IVF (20/58, 33.3%) was reduced compared with vitrified COC (55/90, 62.1%). Vitrified COC showed significantly (P < 0.05) higher developmental ability to develop into the 2-cell (50/90, 57.0%) and blastocyst stages (42/90, 45.9%) compared with vitrified DO [24.8% (16/58) and 18.4% (11/58), respectively]. The vitrified COC developed to term at a high success rate (51/90, 56.7%) being equivalent to the rate obtained with IVF using fresh COC (52/90, 57.8%). Taken together, the current results clearly demonstrate that, in the presence of surrounding cumulus cells, matured mouse oocytes vitrified using calcium-free media and ethylene glycol retain their developmental competence. These findings will contribute to improve oocytes vitrification in not only experimental animals but also in clinical application in human infertility.

[Clinical efficacy of cefpirome sulfate against Bacteroides species, Prevotella species and Porphyromonas species. Society of Anaerobic Bacterial Infections in the fields of obstetrics and gynecology in Gifu]

The injectable cephalosporin cefpirome (CPR) was launched in Japan in 1993. It has widely been used in the various infectious diseases. We therefore studied the clinical and bacteriological efficacy of CPR against infections caused by Bacteroides species, Prevotella species and Porphyromonas species frequently isolated from the obstetric and gynecologic infections. Thirteen institutions were involved in this study which ran from March 1994 to January 1999. The administration dosage of CPR was 2 to 4 gram per day administered by drip infusion or intravenous infusion. The duration of treatment was from 3 to 15 days. The evaluations were performed before and after the treatment. CPR was administered to 194 patients with obstetric and gynecologic infections, and 146 of 194 cases were acceptable for the evaluation of drug efficacy. Bacteroides species were identified in 102 patients. Clinical efficacy in 146 cases was excellent in 12 patients, good in 110, fair in 9 and poor in 15 patients. The eradication rate for Bacteroides species could be in 37 cases out of 54 evaluable cases; Prevotella species in 38 out of 49; and Porphyromonas species in 5 out of 5. The overall assessment of bacteriological efficacy was "eradicated" in 91 cases out of 133 (68.4%). Adverse reactions including abnormal findings in laboratory tests were seen in 8 patients (4.76%). Based on these results, CPR promises efficacy and safety in the treatment of obstetric and gynecologic infections due to Bacteroides species.

Increased expression of plasminogen activator and plasminogen activator inhibitor during liver fibrogenesis of rats: role of stellate cells

BACKGROUND/AIMS

Plasminogen activators and plasminogen activator inhibitors are important regulators of the balance between the proteolytic and antiproteolytic activities that determine extracellular matrix turnover. We examined the expression of plasminogen activator-plasmin system components in experimental liver fibrosis of rats.

METHODS

Liver fibrosis was produced in rats by injecting carbon tetrachloride for 6 to 12 weeks. Gene expression for plasminogen activator inhibitor-1 (PAI-1), urokinase and tissue plasminogen activators (uPA and tPA), urokinase plasminogen activator receptor (uPAR), and transforming growth factor-beta1 (TGF-beta1) was examined by Northern analysis. Western analysis was performed to detect protein expression of PAI-1, uPA and uPAR. An immunohistochemical study was performed to detect the localization of PAI-1. Additionally, primary cultured liver cells were examined by Northern and Western analyses for this protein with or without prior incubation with TGF-beta1.

RESULTS

At 6 weeks, when fibrosis had occurred, uPA and uPAR mRNAs had increased 2.8-fold and 1.8-fold, respectively; PAI-1 and tPA mRNA levels were unchanged. At the cirrhotic stage (9 to 12 weeks), mRNA levels for PAI-1, uPA, uPAR and tPA were all increased. Western analysis also showed increased uPA and uPAR expressions in fibrotic liver, and increased PAI-1, uPA and uPAR expressions in cirrhotic liver. PAI-1 protein was also demonstrated immunohistochemically along sinusoids, vessels, and bile duct cells of normal and fibrotic liver. In liver cell cultures, Kupffer cells, hepatocytes, and especially stellate cells, expressed PAI-1. Expression was enhanced in stellate cells cultured from fibrotic or cirrhotic liver or stimulated in vitro with TGF-beta1.

CONCLUSION

Though increased uPA and uPAR may act on matrix degradation in fibrotic liver, increased PAI-1 together with uPA, uPAR and tPA are associated with overall inhibition of matrix degradation in cirrhotic liver. Hepatic stellate cells are an important source of PAI-1 during liver fibrosis.

Spatial distribution of tissue inhibitor of metalloproteinase-1 mRNA in chronic liver disease

BACKGROUND/AIMS

Tissue inhibitor of metalloproteinase-1, a specific inhibitor of matrix metalloproteinases, plays an important role in the pathogenesis of fibrosis and tumor progression. However, the precise expression of tissue inhibitor of metalloproteinase-1 messenger RNA in human hepatic fibrosis has not yet been defined. We investigated the spatial distribution of tissue inhibitor of metalloproteinase-1 messenger RNA in chronic human liver disease.

METHODS

Northern and in situ hybridization of probes to tissue inhibitor of metalloproteinase-1 messenger RNA were performed in specimens from 16 surgically resected human livers. Immunohistochemical staining of sections for tissue inhibitor of metalloproteinase-1 and immunoelectron microscopy were also performed.

RESULTS

Northern hybridization demonstrated that expression of tissue inhibitor of metalloproteinase-1 messenger RNA was increased 3.9-fold in mild chronic hepatitis, 6.8-fold in moderate chronic hepatitis, and 6.4-fold in cirrhosis, compared with control liver. In situ hybridization showed the expression of tissue inhibitor of metalloproteinase-1 messenger RNA in spindle-shaped cells in the fibrous septa and lobules in chronic hepatitis and cirrhosis; these cells were immunohistochemically positive for a-smooth muscle actin. Immunoelectron microscopy revealed localization of tissue inhibitor of metalloproteinase-1 in between fibers, to the rough endoplasmic reticula of stellate cells located in the lobules and periportal areas, and to fibroblasts in the fibrous septa. These results indicate that tissue inhibitor of metalloproteinase-1 was produced mainly by stellate cells in the specimens of chronic liver diseases.

CONCLUSIONS

Expression of tissue inhibitor of metalloproteinase-1 messenger RNA is increased in hepatic fibrosis and stellate cells are involved primarily in its expression.

Expression of matrix metalloproteinase-13 and tissue inhibitor of metalloproteinase-1 in acute liver injury

BACKGROUND/AIMS

Matrix metalloproteinase-13, one of the principal neutral proteinases capable of cleaving native fibrillar collagens, is important in the degradation and remodeling of extracellular matrix. However, its precise expression in liver injury has not been characterized. We examined the kinetics of the expression of matrix metalloproteinase-13 and one of its specific inhibitors, tissue inhibitor of metalloproteinase-1, in acute liver injury in rats.

METHODS

Acute liver injury was induced by administration of carbon tetrachloride or two different doses of D-galactosamine hydrochloride in Wistar rats. Hepatic matrix metalloproteinase-13 and tissue inhibitor of metalloproteinase-1 mRNA levels were then examined by Northern blotting.

RESULTS

All rats survived after liver injury induced by carbon tetrachloride or low doses of D-galactosamine hydrochloride. However, rats died 5 days after induction of liver injury by high doses of D-galactosamine hydrochloride. In carbon tetrachloride-induced liver injury, matrix metalloproteinase-13 mRNA was transiently increased between 6 h and 1 day after injury. Tissue inhibitor of metalloproteinase-1 mRNA expression was increased between 6 h and 3 days after the peak of matrix metalloproteinase-13 expression. Similar patterns of matrix metalloproteinase-13 and tissue inhibitor of metalloproteinase-1 expression were observed in low-dose D-galactosamine hydrochloride-induced liver injury. In contrast, in high-dose D-galactosamine hydrochloride-induced liver injury, tissue inhibitor of metalloproteinase-1 expression peaked before matrix metalloproteinase-13 expression, which was increased 2 days after injury. Both mRNA levels continued to increase until death.

CONCLUSIONS

Transient expression of matrix metalloproteinase-13, followed by that of tissue inhibitor of metalloproteinase-1, was observed during recovery from acute liver injury induced by carbon tetrachloride and low-dose D-galactosamine hydrochloride. In contrast, disordered expression of matrix metalloproteinase-13 was observed in fatal liver injury caused by high-dose D-galactosamine hydrochloride. These results indicate that matrix metalloproteinase13 plays an important role in the early phase of recovery from liver injury.

Diagnosis of squamous cell carcinoma arising from mature cystic teratoma of the ovary

BACKGROUND

The prognoses of patients with squamous cell carcinoma of the ovary are quite poor. However, preoperative diagnosis is difficult due to the rarity of this tumor and its similarity to mature cystic teratoma (MCT). The objective of this study was to assess the value of tumor markers and clinical characteristics in making a differential diagnosis between MCT and squamous cell carcinoma arising from MCT.

METHODS

Between September 1979 and June 1996, 37 patients with ovarian squamous cell carcinoma arising from MCT were treated by the Tokai Ovarian Tumor Study Group. The authors evaluated tumor markers, tumor size, and age as parameters for differentiation between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was calculated as the sensitivity multiplied by the specificity.

RESULTS

There were significant differences (P < or = 0.0002) in age, tumor size, and levels of squamous cell carcinoma antigen (SCC), CA125, and CEA, as well as a significant difference (P < or = 0.0396) in the CA19-9 level between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was highest for SCC (63.0%), followed by CA125 (50.7%). Receiver operating characteristic (ROC) curves demonstrated that CEA was the best screening marker for squamous cell carcinoma arising from MCT, whereas age and tumor size were better markers than CA125 or CA19-9. The optimal cutoff values for age and tumor size were 45 years and 99 mm, respectively, according to ROC analysis.

CONCLUSIONS

These findings demonstrate that age and tumor size are important factors in making a differential diagnosis. In addition, SCC and CEA levels should be measured in patients age 45 years or older who have an MCT-like ovarian tumor larger than 99 mm in greatest dimension.

Diagnosis of squamous cell carcinoma arising from mature cystic teratoma of the ovary

BACKGROUND

The prognoses of patients with squamous cell carcinoma of the ovary are quite poor. However, preoperative diagnosis is difficult due to the rarity of this tumor and its similarity to mature cystic teratoma (MCT). The objective of this study was to assess the value of tumor markers and clinical characteristics in making a differential diagnosis between MCT and squamous cell carcinoma arising from MCT.

METHODS

Between September 1979 and June 1996, 37 patients with ovarian squamous cell carcinoma arising from MCT were treated by the Tokai Ovarian Tumor Study Group. The authors evaluated tumor markers, tumor size, and age as parameters for differentiation between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was calculated as the sensitivity multiplied by the specificity.

RESULTS

There were significant differences (P < or = 0.0002) in age, tumor size, and levels of squamous cell carcinoma antigen (SCC), CA125, and CEA, as well as a significant difference (P < or = 0.0396) in the CA19-9 level between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was highest for SCC (63.0%), followed by CA125 (50.7%). Receiver operating characteristic (ROC) curves demonstrated that CEA was the best screening marker for squamous cell carcinoma arising from MCT, whereas age and tumor size were better markers than CA125 or CA19-9. The optimal cutoff values for age and tumor size were 45 years and 99 mm, respectively, according to ROC analysis.

CONCLUSIONS

These findings demonstrate that age and tumor size are important factors in making a differential diagnosis. In addition, SCC and CEA levels should be measured in patients age 45 years or older who have an MCT-like ovarian tumor larger than 99 mm in greatest dimension.

Dual expression of matrix metalloproteinase-2 and membrane-type 1-matrix metalloproteinase in fibrotic human livers

We have previously reported increased expression of matrix metalloproteinase-2 (MMP-2) using a rat model of liver fibrosis. However we did not clarify how the precursor of MMP-2 (proMMP-2) was activated. Therefore, we used human liver specimens with chronic hepatitis (CH) and liver cirrhosis (LC) to examine expression of membrane-type-1-MMP (MT1-MMP), which has recently been determined to activate proMMP-2. Northern hybridization studies showed a 5.4- and 1.4-fold increase in MMP-2 expression in CH and LC, respectively, as compared with normal liver. MT1-MMP gene expression simultaneously increased 4.0- and 1.4-fold in CH and LC, respectively. In situ hybridization using 35S-cRNA probes of MMP-2 and MT1-MMP showed prominent silver granules in elongated cells found in the lobules, periportal areas, and fibrous septa of CH and LC samples. These elongated cells expressed alpha-smooth muscle actin by immunohistochemistry. Immunoelectron microscopic examination localized MMP-2 and MT1-MMP to the rough endoplasmic reticulum of stellate cells located in the lobules and periportal areas, or to fibroblasts in the fibrous septa, suggesting that MMP-2 and MT1-MMP were produced by these cells. In addition, cytoplasmic and membranous immunodeposits of both MMPs were found in endothelial cells, Kupffer cells, capillary endothelial cells, and lymphocytes, indicating that activation of proMMP-2 occurs locally. Increased expression of MMP-2 and MT1-MMP was detected in CH and LC, while dual over-expression was found in stellate cells and fibroblasts, possibly resulting in the increase of active MMP-2 in and around these cells. These findings suggest that activated MMP-2 may remodel liver parenchyma during the process of liver fibrosis.

Detection of apoptosis in human endometriotic tissues

To clarify whether apoptosis is involved in endometriosis, we obtained eutopic endometrial tissues along with endometriotic tissues from the uterus (adenomyosis) (n = 12) and from the ovary (n = 12) from patients undergoing gynaecological surgery. Apoptosis-induced DNA fragmentation was detected by the TdT-mediated dUTP-biotin nick-end labelling method, and immunostaining with a monoclonal antibody against the Fas, Le(y) or B-cell leukaemia/lymphoma-2 (bcl-2) was also performed using the same tissue section. Analysis showed that apoptosis was occurring in all the samples of ovarian endometriotic tissue but in only two of the 12 adenomyotic and in five of the 24 eutopic endometrial tissue samples. In none of these cases was apoptosis correlated with phases of the menstrual cycle. The expression of bcl-2 in the eutopic endometrial and adenomyotic tissues was limited to the proliferative phase, and was observed in only one of the 12 cases of ovarian endometriosis. Fas and Ley were expressed randomly across a wide range in both the eutopic and ectopic endometrial tissues. These results suggest that the features of ovarian endometriosis are different from those of adenomyosis and eutopic endometrium in terms of the involvement of apoptosis. In addition, the regulatory mechanism involved in ovarian endometriosis may differ from that in other endometrial cells.

Effects of the mutations (Trp8 --> Arg and Ile15 --> Thr) in human luteinizing hormone (LH) beta-subunit on LH bioactivity in vitro and in vivo

The mutations (Trp8 --> Arg and Ile15 --> Thr) in the human LHbeta -subunit caused by nucleotide point mutations in the LHbeta gene were reported in women with immunologically anomalous LH and menstrual disorders. To estimate the effects of the mutations on LH bioactivity in vitro and in vivo, we constructed a LHbeta gene containing this nucleotide mutation in each site or in both sites by site- directed mutagenesis and analyzed the bioactivities of the mutant LH expressed in Chinese hamster ovary cells. Although no alterations were noted in the receptor-binding activity of LH due to the mutations, the LHs containing the mutations at Trp8 --> Arg and at both sites in the beta-subunit showed a higher biopotency of progesterone production in vitro. The clearance rate from the circulation was faster in vivo in all mutant LHs, which were induced primarily by the mutation at Trp8 --> Arg. However, the mutations did not affect the ability of LH to induce ovulation in vivo. These results indicate that LH consisting of the mutant beta-subunit exhibits hyperbioactivity on steroidogenesis and has a short turnover rate. This may affect the endocrine pathway among women with the mutant LH and lead to menstrual disorders.

Screening of the mutations in luteinizing hormone beta-subunit in patients with menstrual disorders

OBJECTIVE

To evaluate the clinical significance of the LH consisting of a mutant beta-subunit (Trp8 to Arg8 and Ile15 to Thr15).

DESIGN

Clinical and biochemical studies.

SETTING

Fertility center at the University Hospital and its research laboratory.

PATIENTS

Fifty-one patients with menstrual disorders and three homozygote cases and two heterozygote cases of the mutant LH who were reported previously.

INTERVENTIONS

Nucleotide mutations of the LH beta gene in patients with menstrual disorders were screened using techniques of the polymerase chain reaction and restriction fragment length polymorphism. Immunologic and biologic activities of the mutant LH and endocrinologic profiles in the affected women were evaluated.

MAIN OUTCOME MEASURES

Serum LH levels measured with different immunoassay kits; serum FSH and LH on the GnRH test; serum thyroid-stimulating hormone, PRL, T, and androstenedione; ultrasound examination of the ovaries; clinical hyperandrogenic symptoms; and biologic activity of LH.

RESULTS

Two cases of homozygotes and four of heterozygotes affected by the LH beta gene mutations were discovered in the current study through screening of patients with menstrual disorders. Serum LH levels in the homozygote cases were undetectable using a LH immunoassay kit, whereas levels in the heterozygote cases showed reduced detectability with the kit. However, the ratio of the mutant LH values in the bioassay to those in the immunoassay was higher in the homozygote group than that in the control subjects. Response patterns of serum gonadotropins to GnRH in the homozygote were similar to those in patients with polycystic ovary syndrome.

CONCLUSION

The mutations of LH beta-subunit might be related to menstrual disorder in some patients.

Increased expression of matrix metalloproteinase-II in experimental liver fibrosis in rats

Matrix metalloproteinase-II (MMP-II, 72-kd type IV collagenase, or gelatinase) is one of the gene families of zinc enzymes capable of degrading extracellular matrix molecules, and specifically of degrading type IV and V collagens, gelatin, fibronectin, and elastin. In this study, we used both the liver fibrosis model and the reversibility model of experimental cirrhosis to clarify how MMP-II participates in liver fibrosis of rats. To produce fibrosis model, rats received subcutaneous injections of CCl4 twice weekly for 7, 9, or 14 weeks. For the reversibility model, rats were treated with CCl4 three times a week for 8 weeks and killed at 3, 7, 14, 28, or 42 days after discontinuation of treatment. MMP-II gene expression was studied by Northern hybridization technique, and gelatinase activity of MMP-II was examined by zymography using gelatin substrate. At the same time, an immunohistochemical study using anti-type IV collagen antibody was carried out. In liver fibrosis model, nodule formation was established at 14 weeks. Immunodeposit of type IV collagen was increased in wide fibrous septa and was clearly observed along sinusoidal wall. Gene expression of MMP-II increased up to 7 to 12 times compared with that of controls, with the expression rate being maximum at an intermediate stage of fibrosis. Zymography showed the expressions of both 65-kd latent MMP-II, which is confirmed to be activated by adding p-aminophenylmercuric acetate, and 62-kd active MMP-II during fibrosis. The expression of both forms increased 13 to 28 times as the fibrosis progressed.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of two point mutations in the gene coding luteinizing hormone (LH) beta-subunit, associated with immunologically anomalous LH variants

To analyze the structure of LH in three patients with immunologically anomalous LH, the whole coding region of the LH beta-subunit gene was examined. These patients were infertile, and their serum LH levels could not be measured with an immunoassay kit. Immunoblotting of the LH beta-subunit showed no marked changes in the molecular size of LH beta. Genomic DNA was extracted from peripheral lymphocytes of the patients and normal controls, and LH beta genes were amplified by the polymerase chain reaction technique, using primer pairs that are capable of specifically amplifying only the LH beta gene without interference by the CG beta genes. No deletions were observed in the coding regions of the LH beta gene of the patients. Nucleotide sequencing revealed two nucleotide substitutions in the LH beta gene of the patients, which cause amino acid replacements from Trp8 (TGG) to Arg8 (CGG) and Ile15 (ATC) to Thr15 (ACC). Restriction fragment length polymorphism analysis in three families indicated that the affected probands were homozygous, and their family members were heterozygous, except for their husbands. The heterozygotes showed reduced detectability with the LH immunoassay kit. These results suggest that these amino acid replacements are responsible for this immunologically anomalous variant.

Unilateral conjugate gaze palsy due to a lesion of the abducens nucleus. Clinical and neuroradiological correlations

We report a case of left-sided horizontal gaze palsy, ipsilateral adduction weakness, and left peripheral facial weakness, all of which indicate the lesion in the left median pontine tegmentum. The enhanced MRIs revealed a discrete left median pontine tegmental lesion, involving the abducens nucleus, MLF, and facial nerve knee. This lesion spared the area of the left PPRF. Among these structures, the area of the abducens nucleus seems to be responsible for the unilateral horizontal gaze palsy. We are not aware of any previous precise neuroradiological documentation of unilateral paralysis of conjugate gaze due to a lesion of the abducens nucleus by sagittal and horizontal MRIs.

Delayed postanoxic encephalopathy after strangulation. Serial neuroradiological and neurochemical studies

A 13-year-old boy was the victim of attempted strangulation. His condition had returned to normal by the sixth day after the assault; however, from the seventh day, choreoathetosis, dystonia, and marked pseudobulbar paralysis developed in the boy. The computed tomographic scans and T2-weighted magnetic resonance images that were obtained at this time revealed low-density and high-signal intensities in the region of the bilateral putamen and caudate nucleus. These symptoms and the changes in his computed tomographic scans and magnetic resonance images subsided gradually during a 2-month period. Sequential analysis of the cerebrospinal fluid for gamma-aminobutyric acid and dopamine concentrations during his illness revealed reciprocal changes with normal recovery. Because of the delayed onset of neurological changes and the cerebrospinal fluid showing reversible symptoms, the delayed encephalopathy after strangulation had been related to the biochemical alterations that followed anoxia in the vulnerable basal ganglia.

Epileptic seizures in a patient with mitochondrial myopathy, encephalopathy, lactic acidosis and strokelike episodes (MELAS)

This study reports a case of MELAS with epileptic seizure, and reviews the characteristics of seizures in patients with this syndrome. They are characterized by: (1) generalized and/or partial seizures, (2) frequent association with visual symptoms and hemiparesis, and (3) posteriorly predominant EEG abnormalities.

MALE SKIN ISOGRAFTS CAN INDUCE UNRESPONSIVENESS IN FEMALE RATS

Nonsensitized (DA x PVG/c) F1 hybrid female rats regularly accepted male skin isografts. However, almost all F1 females sensitized with male F1 bone marrow cells rejected male skin isografts. Spleen cells taken from sensitized F1 females, either before or after the rejection of male skin isografts, conferred resistance against graft-versus-host (GVH) reactions produced in F1 females by parental PVG/c lymph node cells, but only when the cell donors were male. Repeated injection with bone marrow cells from F1 males failed to cause rejection of established male skin grafts by F1 females. Additional male skin grafts transferred after bone marrow cell injection were also retained. However, if established male skin isografts had been deliberately removed from F1 females before injection of male bone marrow cells, subsequently placed male skin grafts were rejected. Neither spleen cells collected from F1 females bearing established male skin isografts after repeated injection with male bone marrow cells, nor spleen cells obtained from F1 females that had received four consecutive male skin isografts were observed to confer resistance against GVH reactions produced by male PVG/c lymph node cells in F1 female recipients. Splenectomy of prospective F1 female recipients did not confer on them the capacity to reject male skin isografts. These results imply that the placement of a male skin isograft interfered with subsequent attempts to stimulate F1 hybrid females to reject male grafts and to resist GVH reactions produced by lymphocytes from PVG/c males.