Usefulness of Ultrasonography in the Diagnosis and Follow-up of Extracranial Vertebral Artery Dissection.

Extracranial vertebral artery dissection is a cerebrovascular disease that occurs most commonly in young people. A 32-year-old man experienced sudden cervical pain and was diagnosed with left vertebral artery dissection after arterial changes were identified by ultrasonography. The reduction in the size of an intramural hematoma in the left vertebral artery and in the peak systolic velocity were evaluated over time. Computed tomography, magnetic resonance imaging, and cerebral angiography are generally performed to diagnose and follow-up extracranial vertebral artery dissection; however, carotid ultrasonography has an advantage over these modalities by enabling the simultaneous observation of vascular morphology and hemodynamics.

Effect of prior antiplatelet therapy on large vessel occlusion in patients with non-valvular atrial fibrillation newly initiated on apixaban.

INTRODUCTION: We evaluated the effect of prior antiplatelet therapy on large vessel occlusion (LVO) in patients with non-valvular atrial fibrillation (NVAF) newly initiated on apixaban. METHODS: Patients with acute LVO with acute stroke due to NVAF or stenosis with NVAF started on apixaban within 14 days of onset were enrolled. We compared incidence of major bleeding, cerebral hemorrhage, ischemic events, cerebral infarction, and all-cause mortality between patients with and without prior antiplatelet therapy for acute LVO. We also compared these events between patients who continued antiplatelet therapy after onset (continued group) and those who discontinued it (discontinued group). Hazard ratios were estimated after adjusting for confounders; interaction was evaluated considering intravenous thrombolysis (IVT) or endovascular treatment (EVT) according to major bleeding. RESULTS: The study comprised 686 eligible patients (excluded [n = 194]; enrolled [n = 492]). The antiplatelet group consisted of older patients (mean: 79 vs. 76 years; p = 0.006) and had a higher cumulative incidence of major bleeding (7.3% vs. 2.9%, p = 0.003). The incidence of ischemic events and all-cause mortality was similar between the groups. Among the 109 patients in the antiplatelet group, the cumulative incidence of major bleeding, ischemic events, and all-cause mortality was comparable between continued group (n = 26) and discontinued group (n = 83). There were no significant differences between groups with and without IVT/EVT. However, major bleeding occured more frequently in the antiplatelet group without IVT. CONCLUSION: Prior antiplatelet therapy for LVO in patients with NVAF newly initiated on apixaban was associated with major bleeding, which was more frequent in the antiplatelet group without IVT.

Plasma brain natriuretic peptide level on admission predicts long-term outcome in patients with non-traumatic subarachnoid hemorrhage.

INTRODUCTION: Non-traumatic subarachnoid hemorrhage (SAH) is a type of stroke that still has a high mortality rate. Some patients with SAH have electrocardiography (ECG) abnormalities or asymptomatic left ventricular apical ballooning, and requires intervention by cardiologists. However, the impact of cardiac abnormalities after SAH onset remains unclear. We investigated whether ECG abnormalities, myocardial damage, sympathetic nervous activity or echocardiographic left ventricular wall motion abnormalities (WMA) could provide additional risk stratification in patients with SAH. METHODS: We studied 118 SAH patients (78 women, age 63 ± 15) without a history of heart disease. Neurological grade (Hunt and Kosnik Grade) and clinical factors were evaluated. A standard 12-lead ECG, echocardiography and blood samples were obtained within 48 h after SAH onset. ECG abnormalities were defined as abnormal Q wave, ST elevation, giant T-wave inversion or QT prolongation. RESULTS: Twenty of 118 patients (17%) died during the follow-up (35 ± 31 months). Death was significantly associated with higher age (p < 0.0001), neurological grade (p < 0.0001), elevated BNP level (p < 0.0001), increased plasma norepinephrine levels (p < 0.0001) and WMA (p = 0.0070), while ECG abnormalities were not significantly associated. Neurological grade (p < 0.0001), age (p = 0.0047) and BNP (p = 0.0014, hazard ratio 1.0255 for each 1 pg/mL increase in BNP, 95%CI 1.0088 to 1.0499) were independently associated with death. Patients with BNP ≥ 96.6 had a higher risk of death (log- rank p < 0.0001). CONCLUSION: Plasma BNP might provide an additional risk stratification in patients with non-traumatic SAH that requires intervention by cardiologists for both its prevention management after onset.

Cervical Myelopathy Due to Direct Cord Compression by Posterior Inferior Cerebellar Artery Associated with Aberrant Vertebral Artery.

BACKGROUND: The effectiveness of surgical microvascular decompression (MVD) of the vertebral artery (VA) for treating conditions such as trigeminal neuralgia or hemifacial spasm is well known. However, the use of MVD for a case in which the posterior inferior cerebellar artery (PICA) is directly compressing the high cervical cord has not been reported. CASE DESCRIPTION: A 48-year-old male was diagnosed with a rare case of myelopathy due to the PICA directly compressing the high cervical cord. The patient had a C-2 segmental type of VA that penetrated the intradural space at the C1 level. The VA-PICA portion was located just after where the intradural space was penetrated, and the branching PICA strongly and vertically compressed the high cervical cord. CONCLUSIONS: MVD of the PICA was performed, and the patient experienced rapid improvement of myelopathy. The patient immediately improved postoperative day 1 and was doing well at his 1-year follow-up. This is a rare case of the PICA directly compressing the cervical cord and causing myelopathy. MVD of the PICA resulted in good patient recovery.

Increased Resting Energy Expenditure after Endovascular Coiling for Subarachnoid Hemorrhage.

BACKGROUND: Appropriate nutritional care from the acute stage is essential for improved functional outcomes and reduced mortality in patients with subarachnoid hemorrhage (SAH). Although endovascular coiling is increasingly being used as an alternative to neurosurgical clipping and craniotomy for ruptured aneurysms, the resting energy expenditure (REE) of patients treated with this new technique has not been systemically evaluated. METHODS: We measured REE values by indirect calorimetry in 12 SAH patients treated with endovascular coiling. We averaged the REE measurements obtained on days 1 and 7 after endovascular coiling, and then we statistically compared the mean REE values with those in 30 patients with acute cerebral infarction (ACI) by the Wilcoxon rank-sum test (P <.05). Next, we calculated the ratio of measured REE values to the values estimated using the Harris-Benedict equation to adjust for demographic differences in sex, weight, height, and age between the groups. RESULTS: The ratios were significantly higher in SAH patients (median value, 1.12; interquartile range, 1.05-1.23) than in ACI patients (median value, 1.02; interquartile range, .97-1.09). CONCLUSIONS: Because endovascular coiling is less invasive than neurosurgical clipping, the observed increase in REE was attributed to metabolic changes after SAH. To provide optimal nutritional care to SAH patients from the acute stage, clinicians should be aware of this change in REE.

Arteriovenous malformation of the vestibulocochlear nerve.

We describe a rare case of an arteriovenous malformation (AVM) embedded in the vestibulocochlear nerve presenting with subarachnoid hemorrhage (SAH) treated by microsurgical elimination of the main feeding artery and partial nidus volume reduction with no permanent deficits. This 70-year-old woman was incidentally diagnosed 4 years previously with two small unruptured tandem aneurysms (ANs) on the right anterior inferior cerebral artery feeding a small right cerebellopontine angle AVM. The patient was followed conservatively until she developed sudden headache, nausea and vomiting and presented to our outpatient clinic after several days. Magnetic resonance imaging demonstrated findings suggestive of early subacute SAH in the quadrigeminal cistern. A microsurgical flow reduction technique via clipping between the two ANs and partial electrocoagulation of the nidus buried within the eighth cranial nerve provided radiographical devascularization of the ANs with residual AVM shunt flow and no major deficits during the 2.5 year follow-up. This is only the second report of an auditory nerve AVM. In the event of recurrence, reoperation or application of alternative therapies may be considered.

Comparisons of Predictive Equations for Resting Energy Expenditure in Patients with Cerebral Infarct during Acute Care.

BACKGROUND: Estimation of resting energy expenditure (REE) is essential in planning nutrition support. Several equations are used for this estimation in the clinical setting. The purpose of this study was to compare the predictive accuracy of existing equations for REE in patients with cerebral infarct during acute care. METHODS: We assessed the Harris-Benedict, Mifflin, Owen, Japanese simplified, Wang, and Cunningham equations. The Owen and Japanese simplified equations use sex and weight as explanatory variables, the Harris-Benedict and Mifflin equations include sex, weight, age, and height, and the Wang and Cunningham equations use fat-free mass (FFM) measured using bioelectrical impedance technology. Actual REE values were measured by indirect calorimetry on days 2 and 7 and were then averaged. Applying analysis of variance, predictive accuracy was assessed by comparing the predicted and actual values. RESULTS: A total of 30 patients were analyzed. Actual REE values ranged from 796 to 1637 kcal (mean, 1109). The standard deviation of these values was the smallest with the Harris-Benedict equation (99), followed by the Cunningham (165), and Wang (181) equations. The Mifflin equation underestimated REE in females, whereas the Owen and Japanese simplified equations tended to overestimate it. CONCLUSIONS: Based on our results, the Harris-Benedict equation provides the most accurate prediction of REE. In addition, the Cunningham and Wang equations may be useful in long-term care settings involving patients at risk of malnutrition resulting in uneven loss of FFM relative to weight.

Endoscopic surgery for hemorrhagic pineal cyst following antiplatelet therapy: case report.

Pineal cysts of the third ventricle presenting with acute obstructive hydrocephalus due to internal cystic hemorrhage are a rare clinical entity. The authors report a case of a 61-year-old man taking antiplatelet medication who suffered from a hemorrhagic pineal cyst and was treated with endoscopic surgery. One month prior to treatment, the patient was diagnosed with a brainstem infarction and received clopidogrel in addition to aspirin. A small incidental pineal cyst was concurrently diagnosed using magnetic resonance (MR) imaging which was intended to be followed conservatively. The patient presented with a sudden onset of headache and diplopia. On admission, the neurological examination revealed clouding of consciousness and Parinaud syndrome. Computerized tomography (CT) scans demonstrated a hemorrhagic mass lesion in the posterior third ventricle. The patient underwent emergency external ventricular drainage with staged endoscopic biopsy and third ventriculostomy using a flexible videoscope. Histological examination revealed pineal tissue with necrotic change and no evidence of tumor cells. One year later MR imaging demonstrated no evidence of cystic lesion and a flow void between third ventricle and prepontine cistern. In patients with asymptomatic pineal cysts who are treated with antiplatelet therapy, it is important to be aware of the risk of pineal apoplexy. Endoscopic management can be effective for treatment of hemorrhagic pineal cyst with obstructive hydrocephalus.

The use of intraoperative near-infrared indocyanine green videoangiography in the microscopic resection of hemangioblastomas.

BACKGROUND: The authors assessed the usefulness of intraoperative near-infrared indocyanine green videoangiography (ICG-VA) in the microscopic resection of hemangioblastomas. METHODS: From January 2009 to February 2012, nine consecutive patients (seven men, two women) who underwent surgery for hemangioblastomas using intraoperative ICG-VA were included in this study. Surgery was performed on four cystic cerebellar lesions with mural nodules, two solid tumors (one in the cerebellar hemisphere and one in the medulla oblongata), one spinal tumor and multiple tumors in two patients with von Hippel-Lindau disease. Of the nine patients, three were treated for recurrent tumor. The ICG-induced fluorescence images of hemangioblastomas with variable presentation were evaluated. RESULTS: All tumors could be completely removed en bloc. Blood flow in the tumor and tumor-related vessels at the brain surface were clearly detected by ICG-VA in all cases, except one recurrent tumor where postoperative adhesive scar tissue obstructed ICG-induced fluorescence resulting in poor delineation of the blood flow patterns and tumor margins. ICG-VA was also helpful for detecting the multiple small mural nodules within the cyst or the tumors buried under thin gliotic neural tissue despite reduced fluorescence. CONCLUSION: Intraoperative ICG-VA is a safe and easy modality for confirming the vascular flow patterns in hemangioblastomas. In addition, ICG-VA provided useful information for intracystic small lesions or lesions concealed under thin brain tissue in order to accomplish total resection of these tumors.

Dissection of both frontal and parietal branches of the superficial temporal artery for bypass surgery through a single linear skin incision.

BACKGROUND: Double superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery has typically involved more than one linear incision. In this report, we demonstrate how the procedure can be performed through a single linear skin incision over the parietal branch of the STA. METHODS: Initial dissection of the parietal branch and creation of a subcutaneous cavity along the frontal branch were performed using the conventional microscopic method. Detailed additional dissection and isolation of the frontal branch were accomplished with the aid of an endoscopic retractor. RESULTS: This procedure was performed in five patients for harvesting of approximately 8- and 5-cm lengths of the parietal and frontal branches, respectively. The resultant lengths of the harvested vessels were sufficient for anastomotic revascularization of MCA recipient arteries in both the frontal and temporal lobes. CONCLUSION: This method can be safely performed with achievement of a less invasive dissection of the STA and an overall improved cosmetic outcome.

[Clinical study of acute brain swelling during operation for moyamoya disease].

Treatment for moyamoya disease includes direct and indirect anastomosis. During surgery, acute and massive brain swelling has been encountered infrequently just after opening of the dura mater, while mild or moderate brain swelling is frequently found just after opening of the dura mater. Four out of 866 cases operated on by the first author in the last twenty-two years showed acute and massive brain swelling and the operation had to be completed as soon as possible. In the present study, we investigated the cause of acute brain swelling just after opening of the dura mater. Partial pressure of end-tidal carbon dioxide gas (ETCO(2), mmHg) was measured and recorded just before induction of general anesthesia (preETCO(2)) and just after opening of the dura mater (postETCO(2)) in fourteen patients operated on for moyamoya disease. The distance between the opened dural edge and the top of the swelled brain surface (dbs, mm) was also measured. The relationship between increase in ETCO(2) (x, defined as postETCO(2) minus preETCO(2)) and dbs (y) was investigated and it was revealed that there was a significant positive correlation between the two parameters (y=2.59+0.31x, n=14, r=0.65048, p=0.01177<0.05). It means that decrease in carbon dioxide gas tension in various degrees before operation was normalized abruptly by the anesthesiologist and the increase in carbon dioxide gas tension was thought to increase in cerebral blood flow abruptly, resulting in acute brain swelling.

[A de novo distal PICA aneurysm occurring 3 years after clipping of another distal PICA aneurysm: a case report].

Distal posterior inferior cerebellar artery (dPICA) aneurysms are rare with an incidence of approximately 1% of all intracranial aneurysms. The frequent reports of the non-branching aneurysms or tandem aneurysms in an identical artery may be related to the embryology of dPICA and the anterior inferior cerebellar artery which is distinct from other cerebral arteries, as characterized by a thin vessel wall and tortuous course. In this paper, the authors present a case of a 67-year-old man with a ruptured de novo dPICA aneurysm in the tonsillomedullary segment, which occurred 3 years after clipping of a ruptured aneurysm in the identical segment of the dPICA. The patient had a history of smoking and uncontrolled hypertension. He presented with a sudden onset of severe headache and vomiting. On admission computed tomography demonstrated subarachnoid hemorrhage in the left cerebello-medullary cistern with intra-forth ventricular clots. Vertebral angiography demonstrated a saccular dPICA aneurysm just distal from the previous clip. Based on the angiographic characteristics of the aneurysm and the potential difficulty of a second clipping operation, coil embolization of the parent artery was performed. The postoperative course was uneventful except for the presence of hoarseness. The unusual development and location of ruptured de novo dPICA aneurysm may be explainable by uncontrollable risk factors, as well as by the embryological features of dPICA. Careful follow-up neuroimaging studies and management of risk factors should be continued even after complete neck clipping or coil embolization in cases of dPICA aneurysm.

Initiator titration complex formed at datA with the aid of IHF regulates replication timing in Escherichia coli.

The initiation of replication in Escherichia coli is negatively controlled by a mechanism referred to as 'initiator titration', a process by which the initiator protein, DnaA, is titrated to newly replicated binding sequences on the chromosome to reduce the initiation potential for replication. Initiator titration occurs predominantly at the datA locus that binds exceptionally large amounts of DnaA molecules to prevent aberrant initiations. We found that this was enabled by integration host factor (IHF). Within datA, there is a consensus IHF recognition sequence between the two DnaA recognition sequences (DnaA boxes) essential for its function. Binding of IHF to this site was demonstrated both in vitro and in vivo. Disruption of the core sequence in the consensus of the IHF-binding resulted in increased origin concentration as observed in Delta datA cells. Furthermore, the number of DnaA molecules bound to datA was reduced in cells carrying a disruption in the IHF-binding core sequence. The IHF-binding site and the essential DnaA boxes had to be located at a proper distance and orientation to maintain the accurate initiation timing. Therefore, IHF is a unique element in the control of replication initiation that acts negatively at datA, while known to act as a positive regulator at oriC.

[Folic acid reduces the risk of neural tube defects: awareness and folate intake among pregnant women in 2006].

Folic acid plays an important role in proliferating cells and tissues of the fetus. A randomized control trial demonstrated in 1991 that 4 mg of folic acid supplements successfully prevented 72% of recurrence of neural tube defects (NTDs) in women who had had afflicted pregnancy. In 2000, the Japanese Government recommended women of childbearing age to take 400 microgram of folate supplements per day from 4 weeks prior to and 12 weeks after conception. A questionnaire study was performed in pregnant women by post on their awareness of the role folic acid plays, their life style, and folate intake by dietary consumption. Thirty-five percent of 1,251 pregnant women were aware of the important role of folic acid in the critical stage of fetal development and 31% actually took the supplement. Information on folic acid was obtained through mass media in 47% of the women, through the internet in 17%, through healthcare providers in 13% and so forth. The food record analysis revealed that the dietary intake of folic acid averaged 341 microg/day that was 60 microg less than what was recommended by the Government and that 33 of 86 women took the supplement. Overall, a half of pregnant women are required to take 400 microg folate supplement per day. It is to be stressed that primary prevention of NTDs by periconceptional intake of folic acid is a major public health opportunity and that prevention is more important than cure in the management of NTDs.

Trigeminal neuralgia associated with an anomalous artery originating from the persistent primitive trigeminal artery.

A 31-year-old man presented with typical trigeminal neuralgia caused by an anomalous variant type of anterior inferior cerebellar artery (AICA) directly branching from the primitive trigeminal artery (PTA). Three-dimensional computed tomography angiography, magnetic resonance angiography, and magnetic resonance cisternography disclosed that this anomalous artery originated from the PTA and coursed to the AICA territory of the cerebellum. Microvascular decompression surgery disclosed the trigeminal nerve compressed by this AICA variant together with the superior cerebellar artery. These arteries were successfully transpositioned to decompress the nerve. Careful and thorough inspection around the trigeminal nerve verified that the PTA did not conflict with the nerve. This unusual case was caused by compression of the trigeminal nerve from the AICA directly originating from the PTA, without the more common involvement of the PTA.

Correlation between transcriptional expression of survivin isoforms and clinicopathological findings in human colorectal carcinomas.

Survivin, a novel member of the inhibitor of apoptosis protein (IAP) family, has been markedly overexpressed in most types of human carcinoma, and recognized as a potential target in anticancer therapy. In addition, two splice variants of survivin, survivin-2B and survivin-deltaEx3, have recently been identified. However, expression analysis on its splice variants has not been reported in colorectal carcinomas. Therefore, we investigated the transcription levels of survivin and its splice variants in human colorectal carcinomas, and the correlation between transcript expression levels and pathological findings was analyzed. Tumor tissue samples were provided from 52 cases with colorectal adenocarcinoma resected at the Osaka Medical College from 1995 to 1996. Transcription levels were measured by performing quantitative reverse transcription-polymerase chain reaction (RT-PCR) using primer pairs specific for survivin and either of its splice variants, then normalized by the glyceraldehyde 6-phosphate dehydrogenase. The transcription levels of survivin and its splice variants were significantly higher in the tumor tissue samples, and significantly lower in the normal tissue samples. In addition, approximately 40% of the normal tissue samples did not have any survivin expression. The relative expression level of survivin-2B to survivin (survivin-2B/survivin) was significantly higher in the tumor tissue samples than in the normal ones. In contrast, survivin-deltaEx3/survivin revealed no difference between tumor and normal samples. When Comparing the histological disease stages (stage I and II vs. stage III and IV), there were no significant differences in the expression levels of survivin and its splice variants. The expression level of survivin-2B/survivin for stage III and IV was lower than the one for stage I and II. In addition, a higher level of survivin-2B/survivin significantly correlated with a better prognosis in the present series. The present study demonstrates high expression level of survivin and its splice variants, which is relatively specific in tumor tissue and suggests that they have important roles in the progression of human colorectal carcinomas.

Transcriptional expression of survivin and its splice variants in brain tumors in humans.

OBJECT: Survivin, one of the apoptosis inhibitor proteins, has been detected in most cancers in humans. In addition, two splice variants (survivin-2B and survivin-deltaEx3) have been identified. The authors investigated the transcription levels of survivin messenger (m)RNA and its splice variants in nine tumor cell lines, including gliomas, and in 25 brain tumor samples, by performing quantitative reverse transcription-polymerase chain reaction. The correlation between transcript expression levels and pathological findings were also analyzed. METHODS: Transcription levels were measured using primer pairs specific for survivin and either of its splice variants and were normalized to the glyceraldehyde 6-phosphate dehydrogenase. Among the tumor cell lines tested, glioblastoma cell lines showed the highest levels of survivin expression. Among brain tumor samples studied, survivin was preferentially expressed in malignant brain tumors and gliomas. The relative expression level of survivin-deltaEx3/survivin was significantly higher in malignant than in benign brain tumor samples. Expression patterns were dominant for survivin-deltaEx3 in malignant brain tumors and dominant for survivin-2B in benign ones. A significant linear correlation between survivin mRNA expression and MIB-1 labeling index was demonstrated in all brain tumor samples. CONCLUSIONS: The authors' results indicate that quantifying the levels of survivin and its splice variants is useful for the prediction of the cell biological malignancy of gliomas, independent of their pathological features.

The datA locus predominantly contributes to the initiator titration mechanism in the control of replication initiation in Escherichia coli.

Replication of the Escherichia coli chromosome is initiated synchronously from all origins (oriC) present in a cell at a fixed time in the cell cycle under given steady state culture conditions. A mechanism to ensure the cyclic initiation events operates through the chromosomal site, datA, which titrates exceptionally large amounts of the bacterial initiator protein, DnaA, to prevent overinitiation. Deletion of the datA locus results in extra initiations and altered temporal control of replication. There are many other sites on the E. coli chromosome that can bind DnaA protein, but the contribution of these sites to the control of replication initiation has not been investigated. In the present study, seven major DnaA binding sites other than datA have been examined for their influence on the timing of replication initiation. Disruption of these seven major binding sites, either individually or together, had no effect on the timing of initiation of replication. Thus, datA seems to be a unique site that adjusts the balance between free and bound DnaA to ensure that there is only a single initiation event in each bacterial cell cycle. Mutation either in the second or the third DnaA box (a 9 basepair DnaA-binding sequence) in datA was enough to induce asynchronous and extra initiations of replication to a similar extent as that observed with the datA-deleted strain. These DnaA boxes may act as cores for the cooperative binding of DnaA to the entire datA region.

Intravaginal bacterial flora in patients with uterine cervical cancer. High incidence of detection of Gardnerella vaginalis.

Gynecological diseases may affect the growth of vaginal bacterial flora. We investigated the relationship between uterine cervical cancer and the vaginal bacterial flora. In 20 patients with uterine cervical cancer, we investigated the intravaginal bacterial flora, including Gardnerella vaginalis and Mobiluncus spp. In the patients with uterine cervical cancer, there was a mixed flora of aerobes and anaerobes and, of special note, G. vaginalis was detected in 50% of the patients with uterine cervical cancer (10/20). Bacterial vaginosis was present in 8 of these 10 patients (80%). The count of G. vaginalis detected was higher than that of the other coexisting species and was higher in both pre- and postmenopausal patients with uterine cervical cancer than in a control group of pre- and postmenopausal women with benign gynecological diseases. In contrast, none of Mobiluncus spp. was detected. G. vaginalis was detected at a high incidence in patients with uterine cervical cancer, suggesting that the lesions of uterine cervical cancer provide favorable conditions for the growth of G. vaginalis and anaerobes, which leads to bacterial vaginosis.

Susceptibilities of Mycobacterium leprae and M. avium complex to the H202-Fe-mediated halogenation system supplemented with antimicrobial agents

The susceptibilities of Mycobacterium leprae and M. avium complex (MAC) to the H2-O2-Fe-mediated halogenation system supplemented with antimicrobial agents were evaluated by fluorescein diacetate-ethidium bromide (FDA/EB) staining. In the case of M. leprae, the number of greenstained bacteria (intact cells) was reduced in the presence of the H2O2-Fe-mediated halogenation system supplemented with agents possessing antileprosy activity, such as rifampin, 4,4'-diaminodiphenylsulfone (dapsone), clofazimine, and ofloxacin. In the case of the MAC strain, although viable units of the organisms were reduced by the halogenation system alone, the number of greenstained cells in the FDA/EB stain was not reduced, even when the halogenation system was used in combination with ofloxacin. Because stainability of the cells is related to structural and functional intactness of the membrane, differences between M. leprae and the MAC strain imply possible differences in the rigidity of the cell membrane