A polycystic kidney-disease gene homologue required for male mating behaviour in C. elegans

The stereotyped mating behaviour of the Caenorhabditis elegans male is made up of several substeps: response, backing, turning, vulva location, spicule insertion and sperm transfer. The complexity of this behaviour is reflected in the sexually dimorphic anatomy and nervous system. Behavioural functions have been assigned to most of the male-specific sensory neurons by means of cell ablations; for example, the hook sensory neurons HOA and HOB are specifically required for vulva location. We have investigated how sensory perception of the hermaphrodite by the C. elegans male controls mating behaviours. Here we identify a gene, lov-1 (for location of vulva), that is required for two male sensory behaviours: response and vulva location. lov-1 encodes a putative membrane protein with a mucin-like, serine-threonine-rich amino terminus followed by two blocks of homology to human polycystins, products of the autosomal dominant polycystic kidney-disease loci PKD1 and PKD2. LOV-1 is the closest C. elegans homologue of PKD1. lov-1 is expressed in adult males in sensory neurons of the rays, hook and head, which mediate response, vulva location, and potentially chemotaxis to hermaphrodites, respectively. PKD-2, the C. elegans homologue of PKD2, is localized to the same neurons as LOV-1, suggesting that they function in the same pathway.

Sensory regulation of male mating behavior in Caenorhabditis elegans

C. elegans male mating behavior comprises a series of steps: response to contact with the hermaphrodite, backing along her body, turning around her head or tail, location of the vulva, insertion of the two copulatory spicules into the vulva, and sperm transfer. By ablation of male-specific copulatory structures and their associated neurons, we have identified sensory structures and neurons that participate in each of these steps: the sensory rays mediate response to contact and turning; the hook, the postcloacal sensilla, and the spicules mediate vulva location; the spicules also mediate spicule insertion and regulate sperm transfer. Generally, successful completion of each step places the male in a position to receive a cue for the next step in the pathway. However, the high degree of sensory regulation allows the male to execute some steps independently.

Anticonvulsant Medications Extend Worm Life-Span

Genetic studies have elucidated mechanisms that regulate aging, but there has been little progress in identifying drugs that delay aging. Here, we report that ethosuximide, trimethadione, and 3,3-diethyl-2-pyrrolidinone increase mean and maximum life-span of Caenorhabditis elegans and delay age-related declines of physiological processes, indicating that these compounds retard the aging process. These compounds, two of which are approved for human use, are anticonvulsants that modulate neural activity. These compounds also regulated neuromuscular activity in nematodes. These findings suggest that the life-span-extending activity of these compounds is related to the anticonvulsant activity and implicate neural activity in the regulation of aging.

Primary extrapulmonary sugar tumor (PEST): a report of four cases

The cell of origin and direction of differentiation of the clear cell tumor of the lung (the so-called sugar tumor) remains enigmatic. Recognition of HMB-45 immunoreactivity and identification of melanosomes have suggested a relationship to angiomyolipoma of kidney or liver and lymphangiomyoma. This has given rise to the concept that clear cell tumors are neoplasms of so-called perivascular epithelioid cells--PEComas. Herein we report the existence of four similar tumors occurring in extrapulmonary sites, one of which had malignant features. The three benign tumors occurred in females ages 9, 20, and 40 years; two were located in the rectum and one in the vulva. The malignant tumor occurred in the inter-atrial cardiac septum of a 29-year-old man. Common histologic features were a richly vascular organoid architecture, tumor cells with clear to pale eosinophilic cytoplasm, abundant glycogen, and immunoreactivity for HMB 45, but not S100, multiple keratin, neuroendocrine, or muscle markers. Benign tumors demonstrated low mitotic activity, no necrosis, and good circumscription; the malignant tumor showed considerable mitotic activity, necrosis, and an infiltrative growth pattern. Ultrastructurally, glycogen was present, mitochondria were abundant, and membrane-bound lamellated bodies consistent with premelanosomes were present in two cases, and equivocal in one. Because these tumors have light microscopic, immunohistochemical, and electron microscopic features similar to pulmonary sugar tumors, we propose the name primary extrapulmonary sugar tumor (PEST) for them. Although most PEST's are probably benign, malignant forms appear to exist. These cases further support the concept of a family of systemic HMB-45 positive tumors that include sugar tumors, angiomyolipoma of kidney or liver, lymphangiomyomas, and clear-cell myomelanocytic tumors of the falciform ligament/ligamentum teres.

Diagnosis of station and rotation of the fetal head in the second stage of labor with intrapartum translabial ultrasound

OBJECTIVE

To investigate the ability of intrapartum translabial sonography to diagnose fetal station in the second stage of labor.

METHODS

Patients with uncomplicated pregnancies at term gestation with fetuses in vertex presentation in the second stage of labor underwent serial translabial sonography and digital examinations. In a sagittal section of the maternal pelvis, the direction of the head was noted and categorized as downward, horizontal or upward. By rotating the transducer in the transverse plane the cerebral midline echo was also visualized and the rotation of the head was noted. Clinical and ultrasound data were compared using Somer's d-test.

RESULTS

Sixty patients underwent a total of 168 clinical and sonographic examinations. When on the sonogram the fetal head was directed downward, the station assessed clinically was most frequently <or= + 1 cm from the ischial spines (44/57 (77.2%) cases); when the direction was horizontal, the station was most frequently <or= + 2 cm (53/59 (89.8%) cases); when the fetal head was directed upward, the station was usually >or= + 3 cm (46/52 (88.5%) cases). Failure to visualize the cerebral midline or a rotation >or= 45 degrees were associated with a station of + 2 cm or less in 98/103 (95.1%) examinations. Conversely, a rotation of < 45 degrees was associated with a station of + 3 cm or more in 45/65 (69.2%) examinations. All comparisons between clinical and sonographic findings demonstrated a statistically significant relationship (P < 0.0001). The probability of a station + 3 cm or more was particularly high when an upward direction of the head was seen in combination with a rotation of < 45 degrees (40/42 (95.2%) examinations). The interobserver variability (Cohen's kappa 0.795 and 0.727 for station and rotation, respectively; P < 0.001) and intraobserver variability (0.845 for both station and rotation, P < 0.001) suggested good reproducibility of the method.

CONCLUSIONS

Translabial sonography allows a diagnosis of fetal station with an accuracy comparable to that of digital examination and may provide useful information for diagnosing obstructed labor in the second stage as well as assisting in the choice of instrumental delivery.

Frictional properties of human forearm and vulvar skin: influence of age and correlation with transepidermal water loss and capacitance

The dynamic friction coefficient between skin and a Teflon probe and its correlation with age, body weight, height, transepidermal water loss and skin capacitance was studied in vulvar and forearm skin of 44 healthy female volunteers. The friction coefficient of vulvar skin was 0.66 +/- 0.03 (mean +/- SEM) compared to that of forearm skin of 0.48 +/- 0.01. The difference was highly significant (p less than 0.001). Multiple-regression analysis showed that the vulvar skin friction coefficient was significantly correlated with capacitance as an indicator of stratum corneum hydration (p less than 0.01) but not with age, weight, height or transepidermal water loss. It is concluded that the high friction coefficient of vulvar skin may be due to the increased hydration of vulvar skin. Age-related differences seem to exist for transepidermal water loss and friction coefficient in forearm but not in vulvar skin.

Natural history of genital warts

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Pudendal canal syndrome as a cause of vulvodynia and its treatment by pudendal nerve decompression

Notwithstanding many established causes of vulvodynia there still remains an idiopathic group with unknown etiology and variable results of treatment. We present 11 women with idiopathic vulvodynia in whom the etiology could be defined and who were successfully treated. Age varied from 28-53 years. The vulvar pain was associated with stress urinary incontinence in 6/11 patients and all had constipation. Perineal and vulvar hypoesthesia occurred in 6, weak anal reflex in 7 and diminished EMG activity of the external anal sphincter in 3, of the external urethral sphincter in 6 and of the levator ani muscle in 11. There was significant increase (P<0.05) of the pudendal nerve terminal motor latency (PNTML) in all. The motor and sensory change as well as the increased PNTML point to pudendal canal syndrome. Pudendal nerve block, as a diagnostic and therapeutic test, effected temporary pain relief. Pudendal nerve decompression was performed. The inferior rectal nerve was exposed through a para-anal incision, and followed to the pudendal nerve in the pudendal canal. Pudendal canal fasciotomy was done to release the pudendal nerve in the ischiorectal fossa. Vulvar pain disappeared in 9/11 women and stress urinary incontinence in 4/6. Anal reflex was normalized in 5/7 women, and vulvar and perineal hypoesthesia in 4/6. The EMG activity of the external urethral sphincter improved in 4/6, of the external anal sphincter in 2/3 and of the levator ani in 9/11 women. The PNTML was normalized in 9/11 women. In conclusion, pudendal nerve decompression effected relief and improvement in the sensory and motor manifestations of the pudendal nerve in 9/11 women. Two women did not improve due probably to an irreversible damage of the pudendal nerve, or to incomplete pudendal nerve decompression.

A local, high-density, single-nucleotide polymorphism map used to clone Caenorhabditis elegans cdf-1

Ras-mediated signaling is required for induction of vulval cell fates during Caenorhabditis elegans development. By screening for suppressors of the multivulva phenotype caused by constitutively active let-60 ras, we identified the mutation n2527. To clone the gene affected by n2527, we developed a method for high-resolution mapping. We took advantage of the genomic DNA sequence of the N2 strain by using DNA sequencing to scan for single-nucleotide polymorphisms (SNPs) at defined genomic positions of the RC301 strain. An average of one polymorphism per 1.4 kb was detected in predicted intergenic regions. Because of this high frequency, DNA sequencing is an efficient method to scan for SNPs. By alternating between identifying SNPs and mapping n2527 using selected recombinants, we generated an SNP map of progressively higher density. An intensive search for SNPs resulted in a local map with an average marker spacing of approximately 4 kb. This was used to map n2527 to a 9.6-kb interval. The small size of this interval made it feasible to use DNA sequencing to identify the molecular lesion. In principle, this approach can be used for high-resolution mapping of any C. elegans mutation. Furthermore, this approach can be applied to other species as the genomic sequence becomes available. The n2527 mutation affects a previously uncharacterized gene that we named cdf-1, as it encodes a predicted protein with significant similarity to members of the cation diffusion facilitator family.

Metastatic Crohn's disease: case report of an unusual variant and review of the literature

PURPOSE

Metastatic Crohn's disease is a rare complication of Crohn's disease that has been infrequently reported in the literature. We report a case where submammary, inguinal, and perineal disease was observed in a patient many years after a proctocolectomy. The proliferative and polypoid morphology of the cutaneous lesions has not been previously described. In addition, this case describes severe cutaneous metastatic Crohn's disease in the absence of active gastrointestinal disease, which to our knowledge has not been reported in the literature.

RESULTS

A 55-year-old female with a 25-year history of Crohn's disease was investigated and treated over a 12-month period for metastatic Crohn's disease involving the submammary, inguinal, and perineal areas. These proliferative lesions with erythema and ulceration were histologically consistent with metastatic Crohn's disease. Gram and Ziehl Nielsen stains revealed no pathogenic organisms. The use of topical solutions, antibiotics, immunosuppression, and surgery failed to produce any significant benefit. A review of 42 cases of metastatic Crohn's disease in the literature is reported.

CONCLUSION

Cutaneous metastatic Crohn's disease has an extremely variable macroscopic appearance and may be a source of considerable morbidity. It can be present without other significant symptomatology, although it more commonly parallels gastrointestinal disease activity. There are no trials to guide current treatment, which is mainly based on anecdotal reporting.

Gene expression markers for Caenorhabditis elegans vulval cells

The analysis of cell fate patterning during the vulval development of Caenorhabditis elegans has relied mostly on the direct observation of cell divisions and cell movements (cell lineage analysis). However, reconstruction of the developing vulva from EM serial sections has suggested seven different cell types (vulA, vulB1, vulB2, vulC, vulD, vulE, and vulF), many of which cannot be distinguished based on such observations. Here we report the vulval expression of seven genes, egl-17, cdh-3, ceh-2, zmp-1, B0034.1, T04B2.6 and F47B8.6 based on gfp, cfp and yfp (green fluorescent protein and color variants) reporter fusions. Each gene expresses in a specific subset of vulval cells, and is therefore useful as a marker for vulval cell fates. Together, expressions of markers distinguish six cell types, and reveal a strict temporal control of gene expression in the developing vulva.

Multiple parameter assessment of vulvar irritant contact dermatitis

Transepidermal water loss (TEWL), capacitance, pH, blood flow and color reflectance were evaluated for quantifying the irritant response of vulvar and forearm skin to 3% sodium lauryl sulfate in 9 healthy premenopausal women. TEWL, capacitance, pH, blood flow, and all parameters of color reflectance changed significantly in forearm irritant dermatitis. In vulvar irritant dermatitis, however, significant changes were observed only for blood flow and the color reflectance parameters a* and b*. Using the combination of TEWL, capacitance and blood flow, forearm irritant dermatitis was detected with a sensitivity of 84% and a specificity of 100%. In this study, the best combination of parameters to detect vulvar irritant dermatitis was pH, blood flow, a* and b*, which had a sensitivity of 78% and a specificity of 75%. It is concluded that available bioengineering techniques are less suitable to quantify irritant dermatitis in the vulva than in the forearm.

Transformation of the common wart into squamous cell carcinoma in a patient with primary lymphedema

A patient is reported in whom treatment-resistant periungual and subungual warts underwent malignant transformation into squamous cell carcinoma. Similar changes were observed in multiple warts of the vulvar, perianal, and intravaginal as well as cervical area. The tumors that develop were in many instances microinvasive but did not metastasize. The remarkable conversion of a common wart into a squamous cell carcinoma further implicates the human papovavirus in oncogenesis. The specific factors accountable for the malignant change remain completely unknown, but the patient's lymphedema praecox, as well as her severe reaction to vaccinia, and her development of a disseminate systemic Mycobacterium scrofulaceum infection suggest that the critical factor may be one of immunity.