Pyrazinamide resistance in multidrug-resistant Mycobacterium tuberculosis isolates in Japan.

Thirty-six multidrug-resistant (MDR) Mycobacterium tuberculosis isolates collected in Japan were examined for pyrazinamide susceptibility and pyrazinamidase activity, and analysed by pncA sequencing and a hybridization-based line probe assay (LiPA), which was used to detect pncA mutations for the rapid identification of pyrazinamide-resistant isolates. Pyrazinamide resistance was found in 19 (53%) of them. All pyrazinamide-resistant isolates had no pyrazinamidase activity and at least one mutation in pncA. Among the pncA mutations, 11 had not been previously reported. The results of the LiPA were fully consistent with the DNA sequencing results. A majority of MDR M. tuberculosis isolates in Japan were resistant to pyrazinamide.

Relationship between the isoniazid-resistant mutation katGS315T and the prevalence of MDR-/XDR-TB in Osaka, Japan.

OBJECTIVE: To determine the prevalence of katGS315T mutations in isoniazid (INH) resistant Mycobacterium tuberculosis and to elucidate the association of katGS315T mutations with the prevalence of multidrug-resistant tuberculosis (MDR-TB). DESIGN: From 2001 to 2004, 1655 isolates from all newly registered patients who visited the Osaka Prefectural Medical Centre for Respiratory and Allergic Diseases were tested for drug susceptibility. Genotyping was performed using insertion sequence (IS) 6110-restriction fragment length polymorphism (RFLP) in 1629 of 1655 (98.4%) cases. All 145 isolates of INH-resistant M. tuberculosis, including MDR strains, were tested to detect the katGS315T mutation. RESULTS: Five hundred and sixty isolates (34.4%) shared an RFLP pattern. Of the 145 INH-resistant isolates, 18/48 (37.5%) isolates belonging to the RFLP cluster had katGS315T and 23/97 (23.7%) did not have the mutation. Of the 66 MDR-TB cases, 18/29 (62.1%) isolates belonging to the RFLP cluster had katGS315T and 11/37 (29.7%) did not have the mutation. Of the 29 extensively drug-resistant (XDR) TB cases, 17/21 (80.9%) isolates belonging to the RFLP cluster had katGS315T and 3/8 (37.5%) did not have the mutation. CONCLUSION: The clustering rate by IS6110-RFLP was very high among MDR-/XDR-TB isolates with katGS315T. Our study indicates a strong correlation between the katGS315T mutation and the transmission dynamics of MDR-TB, and especially XDR-TB.

Erythematous swelling of the lip associated with Sjögren's syndrome and mimicking cheilitis granulomatosa.

A 64-year-old Japanese woman developed therapy-resistant erythematous swelling of her upper lip. Our tentative clinical diagnosis of cheilitis granulomatosa was ruled out later by the laboratory findings including increased levels of anti-nuclear-antibody (ANA), anti-SSA/Ro antibody, and positive Schirmer test as well as by a histopathological picture showing a dense perivascular infiltration of plasma cells and mononuclear cells in the dermis instead of granulomatous changes. To the best of our knowledge, this is the first patient in whom annular erythema associated with S ogren's syndrome involved only the upper lip and produced clinical features simulating cheilitis granulomatosa.

NMR analysis of type III antifreeze protein intramolecular dimer. Structural basis for enhanced activity.

The structure of a new antifreeze protein (AFP) variant, RD3, from antarctic eel pout (Rhigophila dearborni) with enhanced activity has been determined for the first time by nuclear magnetic resonance spectroscopy. RD3 comprises a unique translational topology of two homologous type III AFP globular domains, each containing one flat, ice binding plane. The ice binding plane of the N domain is located approximately 3.5 A "behind" that of the C domain. The two ice binding planes are located laterally with an angle of 32 +/- 12 degrees between the planes. These results suggest that the C domain plane of RD3 binds first to the ice [1010] prism plane in the <0001> direction, which induces successive ice binding of the N domain in the <0101> direction. This manner of ice binding caused by the unique structural topology of RD3 is thought to be crucial for the significant enhancement of antifreeze activity, especially at low AFP concentrations.

[Detection of rifampin-resistant Mycobacterium tuberculosis by line probe assay (LiPA)].

A recently described reverse hybridization-based line probe assay is used for the rapid detection of the mutations in the rpoB genes of rifampin-resistant Mycobacterium tuberculosis and for the identification of the M. tuberculosis complex. A multicenter study that included 5 laboratories was performed to evaluate the line probe assay in comparison with the in vitro susceptibility test. A total of 406 mycobacteria isolates which were composed of 103 rifampin-resistant and 230 rifampin-susceptible M. tuberculosis isolates, and 73 mycobacteria other than tubercle bacilli (MOTT), were subjected to this study. All 333 M. tuberculosis isolates were discriminated correctly from MOTT bacilli by a line probe assay. Concordance rates with sequencing results for five wild-type probes (S probes) and four specific mutations (R probes) for detecting the mutations in the rpoB genes were both 100%. The overall concordance rate with the in vitro susceptibility testing results was 98.5% (328 of 333 isolates). These results indicate that a line probe assay kit may be useful for the rapid diagnosis of rifampin-resistant tuberculosis.

Functional and morphological studies of photodamaged skin on the hands of middle-aged Japanese golfers.

The skin of golfers' hands provides a suitable model to study the effect of chronic sun exposure, because one of their hands is exposed to the outer environment, especially sunlight, while the other one is always protected by a glove during play. Our purpose was to find out the influence of photodamage on the properties of the skin surface of middle-aged Japanese by using non-invasive methods. We measured hydration state, and water barrier function of the stratum corneum (SC) and the color of the skin of the dorsum of the hands. In a separate study, we evaluated the skin surface contour by using replicas taken from the skin in a slightly stretched or relaxed position. We found a significant decrease in hydration of the skin surface of the exposed skin as compared to that of the protected skin, whereas no such difference was found with transepidermal water loss, a parameter for water barrier function of the SC. Luminance of skin color was also reduced in the sun-exposed skin. Replica analysis revealed that large wrinkles developing in a relaxed position were more prominent on the exposed than on the protected skin, while fine furrows noted in a slightly stretched position were shallower on the former than the latter. The data obtained indicate that the chronically exposed skin of golfers' hands shows morphological and functional changes resulting from long time exposure to the outer environment especially sunlight. Furthermore, bioengineering non-invasive methods are found to be useful to detect early photodamage of the skin in a more quantitative fashion which is rather difficult to demonstrate clinically.

Chitin-binding proteins in invertebrates and plants comprise a common chitin-binding structural motif.

Tachycitin, a 73-residue polypeptide having antimicrobial activity is present in the hemocyte of horseshoe crab (Tachypleus tridentatus). The first three-dimensional structure of invertebrate chitin-binding protein was determined for tachycitin using two-dimensional nuclear magnetic resonance spectroscopy. The measurements indicate that the structure of tachycitin is largely divided into N- and C-terminal domains; the former comprises a three-stranded beta-sheet and the latter a two-stranded beta-sheet following a short helical turn. The latter structural motif shares a significant tertiary structural similarity with the chitin-binding domain of plant chitin-binding protein. This result is thought to provide faithful experimental evidence to the recent hypothesis that chitin-binding proteins of invertebrates and plants are correlated by a convergent evolution process.

Number of cell layers of the stratum corneum in normal skin - relationship to the anatomical location on the body, age, sex and physical parameters.

We counted the number of cell layers in the stratum corneum (SC) of normal skin taken from different anatomical locations of the body of 301 individuals of various ages. Frozen 6 microm thick sections were stained with a 1% aqueous solution of safranin and observed under a microscope after application of 2% KOH solution. There were great variations in the number of SC cell layers (mean +/- SD) according to location and among different individuals. The smallest number was found in genital skin (6 +/- 2), followed in order by skin of the face (9 +/- 2), neck (10 +/- 2), scalp (12 +/- 2), trunk (13 +/- 4), extremities (15 +/- 4) and the palms and soles (47 +/- 24). The heel showed the largest number (86 +/- 36). No definite correlation was found between the number of corneocyte layers and sex of the individual, whereas there was a slight increase in the number of SC layers with age in the skin of the cheek and back, particularly in male individuals. Comparison of these data with those from functional assessments of the SC of the skin from various locations of healthy adults showed that transepidermal water loss, an indicator of SC barrier function, reflected the number of corneocyte cell layers. In contrast, high-frequency conductance, an indicator of the hydration state of the outer SC, did not seem to be under the influence simply of the number of SC cell layers.

Epidemiology and prognosis of plantar melanoma in 62 Japanese patients over a 28-year period.

BACKGROUND: The plantar surface is one of the commonest sites of malignant melanoma in the Japanese; however, the biological behavior is not sufficiently clarified, because of the paucity of long-term studies. We attempted an epidemiologic survey of the cases of plantar melanoma treated in our institute to study the survival rate in the recent period. METHODS: Of the 207 cases of malignant melanoma observed over the past 28 years, 62 patients were diagnosed as having plantar melanoma. The proportion of plantar melanoma to all melanomas, the sex and age of the patients, and the histologic type, stage, and prognosis were evaluated by comparing those registered in the first half (1969-1982) and the second half (1983-1996) of the period. RESULTS: The proportions of plantar melanoma in the first and second half periods were 31% (28 out of 90) and 29% (34 out of 117), respectively. No sex difference in the patients was observed. The mean age of the patients was 67 years. Fifty-one lesions were histologically proven to be acral lentiginous melanoma (ALM), two were superficial spreading melanoma (SSM), and nine were nodular melanoma (NM). Of the nine NMs, eight were registered in the second half period. The heel was affected in 33 (53%), the metatarsal regions in nine (14%), the toes in six (10%), and the arch areas in 14 (23%). The proportion of the weight-bearing areas, including the heel, metatarsal areas, and toes, decreased in the second half period. A comparison of the stages of plantar melanoma showed that, in the first half period, there were 18% of patients with stage IV disease in contrast to none in the second half period. Conversely, the proportion of stage I and II disease was 50% in the second half period, whereas it was only 39% in the first half period. The 5-year survival rates in the first and second half periods were 56% and 71%, respectively. CONCLUSIONS: The prognosis of plantar melanoma has improved recently at our institute. The possible explanation for a trend to better survival in the second half period may be related to a decrease in stage IV disease as well as to an increase in the frequency of diagnosis of early stage disease.

Non-pigmented nodular plantar melanoma in 12 Japanese patients.

In the Japanese, melanoma most commonly involves the plantar surface. Among 61 patients with plantar melanoma, we diagnosed 50 patients as acral lentiginous melanoma (ALM), nine as nodular melanoma, and two as superficial spreading melanoma. Partial or complete loss of pigment was observed in four of the nine nodular melanoma cases and in the nodular portions of eight ALM cases. All 12 such nodular lesions were ulcerated. The clinical diagnosis of malignant melanoma was easily made in the eight patients with ALM by the characteristic pigmentary changes around the nodule. The presence of some remaining pigment was found to be helpful in making the diagnosis in two lesions of nodular melanoma which, at first, had been clinically diagnosed as eccrine poromas. One of two completely amelanotic nodular melanomas was strongly suspected to be a melanoma because there was a history of a pre-existing pigmented macule before the development of the nodule. The other one required histopathological differentiation from Merkel cell carcinoma. Based on these findings and compared with melanoma on other parts of the body, pigmentation noted in the ulcerative nodule of plantar melanoma seems to disappear easily. This causes difficulty in distinguishing it from other skin tumours.

Functional analyses of the stratum corneum in scars. Sequential studies after injury and comparison among keloids, hypertrophic scars, and atrophic scars.

OBJECTIVE: To characterize the functional properties of the stratum corneum (SC) of various scars. DESIGN: A prospective cohort study. SETTING: University hospital medical center. PATIENTS: Thirty-two consecutive patients surgically treated for various skin diseases and 26 consecutive patients with hypertrophic scars or keloids. MAIN OUTCOME MEASURES: Noninvasive bioengineering measurements of functional properties of the SC, such as transepidermal water loss (TEWL), high-frequency conductance, and SC turnover time. RESULTS: The SC barrier function assessed by TEWL was found to be a better parameter for the functional evaluation of scars than the hydration state of the skin surface measured by high-frequency conductometry. In general, the SC on the scars of deeper wounds in the dermis took longer to normalize functionally than the SC on the scars of superficial wounds, especially on the high compared with the abdomen. Thus, elevated levels of TEWL observed on scars at the donor sites of split-thickness grafts normalized between 200 and 400 days in contrast to fewer than 50 days for those of subepidermal erosions. Both TEWL and high-frequency conductance remained high in hypertrophic scars and keloids, and the SC involved showed a faster turnover time than that of adjacent normal skin. CONCLUSIONS: Scars, a proliferative change of the dermis, can be objectively evaluated according to functional abnormalities of the SC, because the dermis has a close relationship with the epidermis and with the SC. The functional characteristics of the SC of fresh scars and those of hypertrophic scars and keloids resemble those of retinoid-treated skin, rather than those found in epidermal hyperproliferative conditions such as psoriasis and dermatitis.

Epidemiology and prognosis of subungual melanoma in 34 Japanese patients.

The incidence of malignant melanoma is much lower in the Japanese than in caucasians. However, amongst the various types of malignant melanoma, the subungual and periungual sites are commonly found in the Japanese. One hundred and fifty-one cases of cutaneous malignant melanoma were seen over a 25-year period at our hospital. We found that, in 34 patients (23%), the subungual region was involved, a high frequency for one institution. We have analysed these patients and looked at their treatment. The finger nails were affected in 21 cases (62%) and the toe nails in 13 cases (38%). The thumb nails or great toe nails were affected in 25 of the 34 patients (73%). In 25 patients, histopathological features of acral lentiginous melanoma were found, with four cases of superficial spreading melanoma and five of nodular amelanotic melanoma. Of the latter group, four mimicked fibrous histiocytic tumour, and one was a desmoplastic malignant melanoma. The proportion of patients presenting with stage III disease decreased after 1982, with a corresponding increase in patients whose tumour thickness was less than 4 mm (stage II). Concurrently, the prognosis for subungual malignant melanoma improved. The 5-year survival rate in each of the periods 1969-82 and 1983-93 was 53 and 87%, respectively. This is similar to that found in plantar malignant melanoma and is felt to be due to a greater public awareness of the condition and to the introduction of effective chemotherapy (the DTIC-AC nitrosurea-vincristine (DAV) regimen). Although the frequency of malignant melanoma is rather low in the Japanese, our data indicate that there is a high incidence of subungual malignant melanoma. Public awareness of the early stage of malignant melanoma seems to have improved prognosis.

Congenital plantar melanocytic nevus with satellite lesions.

We report a case of a congenital melanocytic nevus accompanied by a mucous cyst and satellite pigmented macules on the undersurface of the left great toe in a 17-year-old Japanese man. Myxoid change was confirmed by the discharge of viscous liquid when conducting biopsy of the tumor. Besides such an unusual clinical feature of the tumor, accompanying satellite lesions led us initially to consider the possibility of malignant melanoma. However, a biopsy specimen obtained from the tumor revealed the typical features of intradermal type melanocytic nevus. In a specimen obtained from the satellite pigmented lesion, there was a small mass of nevus cells underneath the basement membrane zone, suggestive of having originated from the spread of nevus cells through lymphatic vessels.

Clinicopathological study of acral melanoma in situ in 44 Japanese patients.

BACKGROUND: Acral lentiginous melanoma (ALM) has been a major focus of interest in Japan in the last 2 decades. A remarkable improvement recently made in the prognosis of ALM at our institution may possibly be explained by early detection including melanoma in situ. OBJECTIVE: We have retrospectively studied 44 cases of melanoma in situ in the past 25 years from 1970 to 1994, 61% of which have been seen in the last 5 years. RESULTS: Of 190 cases of invasive malignant melanoma including 20 melanomas involving the mucous membrane, 96 were ALM. Accordingly, the number of cases of melanoma in situ involving the acral regions was also prominent. Of 44 melanomas in situ, 29 occurred in the acral regions. Eight lesions localized on the face were compatible with lentigo maligna both clinically and histologically. All 6 mucosal lesions occurred on the oral mucosa. The remaining lesion appeared on the back of a psoriatic patient treated with photochemotherapy. Forty-two specimens showed histologically a lentiginous proliferation including atypical solitary cells within the lower portion of the epidermis, especially in the basal layer. The remaining 2 specimens were histologically of the pagetoid type. CONCLUSION: Corresponding to the fact that ALM are predominant in the Japanese, the most common sites of melanoma in situ are also the acral regions.

Nodular melanoma in 62 Japanese patients: influence of initial surgical treatment on local recurrence and prognosis.

The incidence of malignant melanoma is much lower in Japanese than in Caucasians, and the commonest type of melanoma in Japanese is acral lentiginous melanoma (ALM). In contrast to the improved prognosis noted in ALM, it is now of increasing concern that there is a rise in both the frequency and mortality of nodular melanoma. During the 25 years from 1970 to 1994, we observed 190 patients with melanoma, including 62 nodular melanomas and 96 ALM, at the Department of Dermatology, Tohoku University Hospital, Sendai, Japan. We retrospectively reviewed the recurrence and survival rates of nodular melanoma observed. The proportion of nodular melanoma, once comprising only 24% of all melanomas, showed a sharp increase to 40% after 1982. The anatomical sites of the primary tumor were the hands and feet (29%), extremities excluding hands and feet (27%), head and neck (23%), and trunk (21%). Comparison of the stages of nodular melanoma when diagnosed showed that the proportion of stage III remained highest throughout the whole period, but that of stage II melanomas increased after 1982. After treatment, local recurrence occurred far more frequently in nodular melanoma (19%) than in ALM (1%). The prognosis of nodular melanoma was also less favorable than that of ALM, although it slightly improved after 1982; the 5-year survival rates before and after 1982 were 34 and 50%, respectively. Twenty-eight patients with nodular melanoma had underwent simple excision or incisional biopsy of the primary tumor at another institution and were later referred to us for further intensive care or for the treatment of local recurrence and/or metastases.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrokeratosis paraneoplastica (Bazex syndrome) associated with primary cutaneous squamous cell carcinoma of the lower leg, vitiligo and alopecia areata.

We report a case of acrokeratosis paraneoplastica (AP; Bazex syndrome), characterized by typical palmoplantar hyperkeratosis and psoriasiform scaly erythema of the acral regions, associated with primary cutaneous squamous cell carcinoma (SCC) on the left lower leg. This 54-year-old Japanese man subsequently developed vitiligo, and alopecia areata of the scalp. Serial monitoring of squamous cell carcinoma antigen (SCC-Ag) demonstrated that the severity of the clinical manifestations of AP paralleled the serum concentrations of SCC-Ag. We suggest that an immune-mediated mechanism underlies the development of AP in this patient.

Oral mucosa malignant melanoma in situ with involvement of the perioral skin.

A 66-year-old Japanese woman had a pigmented macule spreading from the internal aspect of the cheek to the vermilion border and perioral skin. Histology was that of in situ malignant melanoma. This case appears to be unique as it implies a longer period of radial growth than is usually observed in malignant melanoma of the oral mucosa.